US11583306B2 - Surgical instruments with articulating shafts - Google Patents

Abstract

The present disclosure is directed to end effectors. An end effector includes an outer shaft extending along a longitudinal axis and an inner shaft partially located within the outer shaft. The end effector may include an ultrasonic blade. The inner shaft may include biased and unbiased portions. The inner shaft and outer shaft may be translatable relative to one another. At one translatable position, the biased portion of the inner shaft may be located within the outer shaft and the unbiased portion may be substantially straight along the longitudinal axis. At another translatable position, the biased portion of the inner shaft may be located outside of and distally positioned from the outer shaft such that the biased portion of the inner shaft is bent away from the longitudinal axis.

Description

PRIORITY

This application is a divisional application claiming priority under 35 U.S.C. § 121 to U.S. patent application Ser. No. 15/187,553, entitled SURGICAL INSTRUMENTS WITH ARTICULATING SHAFTS, filed Jun. 20, 2016, now U.S. Patent Application Publication No. 2016/0296251, which is a divisional application claiming priority under 35 U.S.C. § 121 to U.S. patent application Ser. No. 13/538,588, entitled SURGICAL INSTRUMENTS WITH ARTICULATING SHAFTS, filed Jun. 29, 2012, which issued on Jul. 19, 2016 as U.S. Pat. No. 9,393,037, the entire disclosures of which are hereby incorporated by reference herein.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is also related to the following, U.S. patent applications, which are incorporated herein by reference in their entirety:

U.S. patent application Ser. No. 13/539,096, entitled HAPTIC FEEDBACK DEVICES FOR SURGICAL ROBOT, now U.S. Pat. No. 9,198,714;

U.S. patent application Ser. No. 13/539,110, entitled LOCKOUT MECHANISM FOR USE WITH ROBOTIC ELECTROSURGICAL DEVICE, now U.S. Pat. No. 9,326,788;

U.S. patent application Ser. No. 13/539,117, entitled CLOSED FEEDBACK CONTROL FOR ELECTROSURGICAL DEVICE, now U.S. Pat. No. 9,226,767;

U.S. patent application Ser. No. 13/538,601, entitled ULTRASONIC SURGICAL INSTRUMENTS WITH DISTALLY POSITIONED TRANSDUCERS,” now U.S. Patent Application Publication No. 2014/0005702;

U.S. patent application Ser. No. 13/538,700, entitled SURGICAL INSTRUMENTS WITH ARTICULATING SHAFTS, now U.S. Pat. No. 9,408,622;

U.S. patent application Ser. No. 13/538,711, entitled ULTRASONIC SURGICAL INSTRUMENTS WITH DISTALLY POSITIONED JAW ASSEMBLIES, now U.S. Pat. No. 9,351,754;

U.S. patent application Ser. No. 13/538,720, entitled SURGICAL INSTRUMENTS WITH ARTICULATING SHAFTS, now U.S. Patent Application Publication No. 2014/0005705;

U.S. patent application Ser. No. 13/538,733, entitled ULTRASONIC SURGICAL INSTRUMENTS WITH CONTROL MECHANISMS, now U.S. Pat. No. 9,820,768; and

U.S. patent application Ser. No. 13/539,122, entitled SURGICAL INSTRUMENTS WITH FLUID MANAGEMENT SYSTEM, now U.S. Pat. No. 9,238,045.

BACKGROUND

Various embodiments are directed to surgical devices including various articulatable shafts for use with surgical devices.

Ultrasonic surgical devices, such as ultrasonic scalpels, are used in many applications in surgical procedures by virtue of their unique performance characteristics. Depending upon specific device configurations and operational parameters, ultrasonic surgical devices can provide substantially simultaneous transection of tissue and homeostasis by coagulation, desirably minimizing patient trauma. An ultrasonic surgical device comprises a proximally-positioned ultrasonic transducer and an instrument coupled to the ultrasonic transducer having a distally-mounted end effector comprising an ultrasonic blade to cut and seal tissue. The end effector is typically coupled either to a handle and/or a robotic surgical implement via a shaft. The blade is acoustically coupled to the transducer via a waveguide extending through the shaft. Ultrasonic surgical devices of this nature can be configured for open surgical use, laparoscopic, or endoscopic surgical procedures including robotic-assisted procedures.

Ultrasonic energy cuts and coagulates tissue using temperatures lower than those used in electrosurgical procedures. Vibrating at high frequencies (e.g., 55,500 times per second), the ultrasonic blade denatures protein in the tissue to form a sticky coagulum. Pressure exerted on tissue by the blade surface collapses blood vessels and allows the coagulum to form a hemostatic seal. A surgeon can control the cutting speed and coagulation by the force applied to the tissue by the end effector, the time over which the force is applied and the selected excursion level of the end effector.

Also used in many surgical applications are electrosurgical devices. Electrosurgical devices apply electrical energy to tissue in order to treat the tissue. An electrosurgical device may comprise an instrument having a distally-mounted end effector comprising one or more electrodes. The end effector can be positioned against tissue such that electrical current is introduced into the tissue. Electrosurgical devices can be configured for bipolar or monopolar operation. During bipolar operation, current is introduced into and returned from the tissue by active and return electrodes, respectively, of the end effector. During monopolar operation, current is introduced into the tissue by an active electrode of the end effector and returned through a return electrode (e.g., a grounding pad) separately located on a patient's body. Heat generated by the current flow through the tissue may form haemostatic seals within the tissue and/or between tissues and thus may be particularly useful for sealing blood vessels, for example. The end effector of an electrosurgical device sometimes also comprises a cutting member that is movable relative to the tissue and the electrodes to transect the tissue.

Electrical energy applied by an electrosurgical device can be transmitted to the instrument by a generator. The electrical energy may be in the form of radio frequency (“RF”) energy. RF energy is a form of electrical energy that may be in the frequency range of 300 kHz to 1 MHz. During its operation, an electrosurgical device can transmit low frequency RF energy through tissue, which causes ionic agitation, or friction, in effect resistive heating, thereby increasing the temperature of the tissue. Because a sharp boundary may be created between the affected tissue and the surrounding tissue, surgeons can operate with a high level of precision and control, without sacrificing un-targeted adjacent tissue. The low operating temperatures of RF energy may be useful for removing, shrinking, or sculpting soft tissue while simultaneously sealing blood vessels. RF energy may work particularly well on connective tissue, which is primarily comprised of collagen and shrinks when contacted by heat.

In many cases it is desirable to utilize an ultrasonic blade that is curved or otherwise asymmetric. Currently, asymmetric blades are machined into a curved state. Balancing these blades (e.g., minimizing transverse vibration) is accomplished by machining notches or other features into the blades at key locations. Selecting the locations of the notches or other features, as well as the machining itself, adds greatly to the cost and complexity of the blades.

With respect to both ultrasonic and electrosurgical devices, it is often desirable for clinicians to articulate a distal portion of the instrument shaft in order to direct the application of ultrasonic and/or RF energy. Bringing about and controlling such articulation, however, is often a considerable challenge.

DRAWINGS

The features of the various embodiments are set forth with particularity in the appended claims. The various embodiments, however, both as to organization and methods of operation, together with advantages thereof, may best be understood by reference to the following description, taken in conjunction with the accompanying drawings as follows:

FIG.1 illustrates one embodiment of a surgical system including a surgical instrument and an ultrasonic generator.

FIG.2 illustrates one embodiment of the surgical instrument shown inFIG.1.

FIG.3 illustrates one embodiment of an ultrasonic end effector.

FIG.4 illustrates another embodiment of an ultrasonic end effector.

FIG.5 illustrates an exploded view of one embodiment of the surgical instrument shown inFIG.1.

FIG.6 illustrates a cut-away view of one embodiment of the surgical instrument shown inFIG.1.

FIG.7 illustrates various internal components of one example embodiment of the surgical instrument shown inFIG.1

FIG.8 illustrates a top view of one embodiment of a surgical system including a surgical instrument and an ultrasonic generator.

FIG.9 illustrates one embodiment of a rotation assembly included in one example embodiment of the surgical instrument ofFIG.1.

FIG.10 illustrates one embodiment of a surgical system including a surgical instrument having a single element end effector.

FIG.11 is a perspective view of one embodiment of an electrical energy surgical instrument.

FIG.12 is a side view of a handle of one embodiment of the surgical instrument ofFIG.11 with a half of a handle body removed to illustrate some of the components therein.

FIG.13 illustrates a perspective view of one embodiment of the end effector of the surgical instrument ofFIG.11 with the jaws open and the distal end of an axially movable member in a retracted position.

FIG.14 illustrates a perspective view of one embodiment of the end effector of the surgical instrument ofFIG.11 with the jaws closed and the distal end of an axially movable member in a partially advanced position.

FIG.15 illustrates a perspective view of one embodiment of the axially moveable member of the surgical instrument ofFIG.11.

FIG.16 illustrates a section view of one embodiment of the end effector of the surgical instrument ofFIG.11.

FIG.17 illustrates a section a perspective view of one embodiment of a cordless electrical energy surgical instrument.

FIG.18A illustrates a side view of a handle of one embodiment of the surgical instrument ofFIG.17 with a half handle body removed to illustrate various components therein.

FIG.18B illustrates an RF drive and control circuit, according to one embodiment.

FIG.18C illustrates the main components of the controller, according to one embodiment.

FIG.19 illustrates a block diagram of one embodiment of a robotic surgical system.

FIG.20 illustrates one embodiment of a robotic arm cart.

FIG.21 illustrates one embodiment of the robotic manipulator of the robotic arm cart ofFIG.20.

FIG.22 illustrates one embodiment of a robotic arm cart having an alternative set-up joint structure.

FIG.23 illustrates one embodiment of a controller that may be used in conjunction with a robotic arm cart, such as the robotic arm carts ofFIGS.19-22.

FIG.24 illustrates one embodiment of an ultrasonic surgical instrument adapted for use with a robotic system.

FIG.25 illustrates one embodiment of an electrosurgical instrument adapted for use with a robotic system.

FIG.26 illustrates one embodiment of an instrument drive assembly that may be coupled to a surgical manipulator to receive and control the surgical instrument shown inFIG.24.

FIG.27 illustrates another view of the instrument drive assembly embodiment ofFIG.26 including the surgical instrument ofFIG.24.

FIG.28 illustrates another view of the instrument drive assembly embodiment ofFIG.26 including the electrosurgical instrument ofFIG.25.

FIGS.29-31 illustrate additional views of the adapter portion of the instrument drive assembly embodiment ofFIG.26.

FIGS.32-34 illustrate one embodiment of the instrument mounting portion ofFIGS.24-25 showing components for translating motion of the driven elements into motion of the surgical instrument.

FIGS.35-37 illustrate an alternate embodiment of the instrument mounting portion ofFIGS.24-25 showing an alternate example mechanism for translating rotation of the driven elements into rotational motion about the axis of the shaft and an alternate example mechanism for generating reciprocating translation of one or more members along the axis of theshaft538.

FIGS.38-42 illustrate an alternate embodiment of the instrument mounting portionFIGS.24-25 showing another alternate example mechanism for translating rotation of the driven elements into rotational motion about the axis of the shaft.

FIGS.43-46A illustrate an alternate embodiment of the instrument mounting portion showing an alternate example mechanism for differential translation of members along the axis of the shaft (e.g., for articulation).

FIGS.46B-46C illustrate one embodiment of a tool mounting portion comprising internal power and energy sources.

FIG.47 illustrates a schematic cross-sectional view of a portion of one example embodiment of an ultrasonic medical instrument comprising first, second and third waveguide portions, where the second waveguide portion is substantially ½ of a resonant-longitudinal-wavelength long.

FIG.47A illustrates cross sections for two example embodiments of the second waveguide portion ofFIG.47.

FIG.48 illustrates a schematic cross-sectional view of a portion of one example embodiment of an ultrasonic medical instrument comprising first and second waveguide portions, where the first waveguide portion spans multiple ½ resonant longitudinal wavelengths.

FIG.49 illustrates a schematic cross-sectional view of one example embodiment of an ultrasonic waveguide for use with a medical instrument and comprising first and second waveguide portions, where a first waveguide portion is joined to a second waveguide portion by a dowel press fit.

FIG.50 illustrates a schematic cross-sectional view of one example embodiment of an ultrasonic waveguide for use with a medical instrument and comprising first and second waveguide portions, where the first waveguide portion is joined to the second waveguide portion by a ball-and-socket type attachment.

FIG.51 illustrates a schematic cross-sectional view of a portion of another embodiment of an ultrasonic medical instrument comprising a medical ultrasonic waveguide having a length and including a proximal waveguide portion and a distal waveguide portion.

FIG.52 illustrates one embodiment of an ultrasonic blade comprising a proximal straight section and a distal curved section.

FIGS.53-56 illustrate additional views of the ultrasonic blade ofFIG.52.

FIGS.57 and58 illustrate two example ultrasonic blades balanced as described herein.

FIG.59 illustrates another embodiment of an ultrasonic blade embodiment having a curved section with a different subtended angle and radius of curvature.

FIG.60 illustrates a chart showing the balance of an example blade having a one-half wavelength curved section similar to the blade embodiment ofFIG.59.

FIG.61 illustrates one embodiment of an articulatable shaft that may be articulated utilizing nodal flanges.

FIG.62 illustrates one embodiment of the shaft with portions of the shaft transparent so as to show a waveguide.

FIGS.63-65 illustrate one embodiment of the waveguide ofFIG.62 showing the operation of control members.

FIGS.66-67 illustrate one embodiment of a manual or handheld surgical instrument utilizing the shaft described above.

FIG.68 illustrates one embodiment of the end effector and a distal portion of the shaft showing a pivotable clamp arm.

FIGS.69-71 illustrate one embodiment of a shaft for a surgical instrument, the shaft having a rigid outer shaft and a biased inner shaft.

FIGS.72-74 illustrate one embodiment of the biased inner shaft where biasing is provided by leaf springs.

FIGS.75-76 illustrate another embodiment of a shaft comprising a biased inner shaft and a rigid outer shaft.

FIGS.77 and78 illustrate one embodiment of the shaft and biased inner shaft ofFIGS.75-76 used with an alternate waveguide.

FIGS.79-81 illustrate another example embodiment of a shaft for use with a surgical instrument, the shaft having a rigid outer shaft and a biased inner shaft.

FIGS.82-83 illustrate one embodiment of a distal portion of a surgical instrument comprising a curved ultrasonic blade.

DESCRIPTION

Various embodiments are directed to an ultrasonic blade for use with a surgical instrument. The ultrasonic blade may comprise a proximally positioned straight section extending along a longitudinal axis and a distally positioned curved section coupled to the straight section and curved away from the longitudinal axis. The curved section may define a radius of curvature and may subtend a first angle. The point of tangency between the curved section and the straight section may be at either a node or an anti-node of the ultrasonic blade. The ultrasonic blade may be balanced, for example, based on properties of the curved section. A balanced ultrasonic blade may have vibrational modes that are purely and/or substantially longitudinal (e.g., in the direction of the longitudinal axis). To achieve balance, the ultrasonic blade may be constructed, as described above, such that a node and/or anti-node occurs at the point of tangency when the ultrasonic blade is driven at a resonant frequency. In some example embodiments, all or a portion of the proximally positioned straight section may be considered all or part of a waveguide extending proximally from the ultrasonic blade to a transducer, as described herein.

Some embodiments are directed to a surgical instrument comprising an end effector and an articulatable shaft extending along a longitudinal axis. The shaft may comprise a flexible portion. A waveguide is acoustically coupled to the ultrasonic blade and extends proximally from the blade through the shaft. The waveguide may comprise a bendable waveguide portion positioned on the longitudinal axis at about the position of the flexible portion of the shaft. The waveguide may also comprise first and second flanges positioned at nodes of the waveguide. The first flange may be positioned distally from the bendable waveguide portion, with the second flange positioned proximally from the bendable waveguide portion. A first control member may be coupled to the first flange and extend proximally through the second flange and shaft. Proximal translation of the first control member may pull the first flange proximally, causing the shaft and waveguide to pivot away from the longitudinal axis towards the first control member.

Other embodiments are directed to a surgical instrument comprising an end effector to treat tissue along with outer and inner shafts that are translatable relative to one another along a longitudinal axis. The inner shaft comprises a biased portion that is biased to bend away from the longitudinal axis in a first direction. When the biased portion of the inner shaft is within the outer shaft, the inner and outer shafts may be substantially straight along the longitudinal axis. When the biased portion of the inner shaft is outside of the outer shaft (e.g., positioned distally from the inner shaft) the inner shaft, and end effector, may pivot away from the longitudinal axis in the first direction.

In additional embodiments, a surgical instrument comprises a shaft extending along a longitudinal axis with an ultrasonic blade positioned therein. The ultrasonic blade may comprise a proximally positioned straight section and a distally positioned curved section. The ultrasonic blade may be translatable along the longitudinal axis relative to the shaft from a first position where the curved section of the blade extends from a distal end of the shaft to a second position where the curved section of the blade is at least partially contained within the shaft.

Reference will now be made in detail to several embodiments, including embodiments showing example implementations of manual and robotic surgical instruments with end effectors comprising ultrasonic and/or electrosurgical elements. Wherever practicable similar or like reference numbers may be used in the figures and may indicate similar or like functionality. The figures depict example embodiments of the disclosed surgical instruments and/or methods of use for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative example embodiments of the structures and methods illustrated herein may be employed without departing from the principles described herein.

FIG.1 is a right side view of one embodiment of an ultrasonicsurgical instrument10. In the illustrated embodiment, the ultrasonicsurgical instrument10 may be employed in various surgical procedures including endoscopic or traditional open surgical procedures. In one example embodiment, the ultrasonicsurgical instrument10 comprises ahandle assembly12, anelongated shaft assembly14, and anultrasonic transducer16. Thehandle assembly12 comprises atrigger assembly24, adistal rotation assembly13, and aswitch assembly28. Theelongated shaft assembly14 comprises anend effector assembly26, which comprises elements to dissect tissue or mutually grasp, cut, and coagulate vessels and/or tissue, and actuating elements to actuate theend effector assembly26. Thehandle assembly12 is adapted to receive theultrasonic transducer16 at the proximal end. Theultrasonic transducer16 is mechanically engaged to theelongated shaft assembly14 and portions of theend effector assembly26. Theultrasonic transducer16 is electrically coupled to agenerator20 via acable22. Although the majority of the drawings depict a multipleend effector assembly26 for use in connection with laparoscopic surgical procedures, the ultrasonicsurgical instrument10 may be employed in more traditional open surgical procedures and in other embodiments, may be configured for use in endoscopic procedures. For the purposes herein, the ultrasonicsurgical instrument10 is described in terms of an endoscopic instrument; however, it is contemplated that an open and/or laparoscopic version of the ultrasonicsurgical instrument10 also may include the same or similar operating components and features as described herein.

In various embodiments, thegenerator20 comprises several functional elements, such as modules and/or blocks. Different functional elements or modules may be configured for driving different kinds of surgical devices. For example, anultrasonic generator module21 may drive an ultrasonic device, such as the ultrasonicsurgical instrument10. In some example embodiments, thegenerator20 also comprises an electrosurgery/RF generator module23 for driving an electrosurgical device (or an electrosurgical embodiment of the ultrasonic surgical instrument10). In various embodiments, thegenerator20 may be formed integrally within thehandle assembly12. In such implementations, a battery would be co-located within thehandle assembly12 to act as the energy source.FIG.18A and accompanying disclosures provide one example of such implementations.

In some embodiments, the electrosurgery/RF generator module23 may be configured to generate a therapeutic and/or a sub-therapeutic energy level. In the example embodiment illustrated inFIG.1, thegenerator20 includes acontrol system25 integral with thegenerator20, and afoot switch29 connected to the generator via acable27. Thegenerator20 may also comprise a triggering mechanism for activating a surgical instrument, such as theinstrument10. The triggering mechanism may include a power switch (not shown) as well as afoot switch29. When activated by thefoot switch29, thegenerator20 may provide energy to drive the acoustic assembly of thesurgical instrument10 and to drive theend effector18 at a predetermined excursion level. Thegenerator20 drives or excites the acoustic assembly at any suitable resonant frequency of the acoustic assembly and/or derives the therapeutic/sub-therapeutic electromagnetic/RF energy.

In one embodiment, the electrosurgical/RF generator module23 may be implemented as an electrosurgery unit (ESU) capable of supplying power sufficient to perform bipolar electrosurgery using radio frequency (RF) energy. In one embodiment, the ESU can be a bipolar ERBE ICC 350 sold by ERBE USA, Inc. of Marietta, Ga. In bipolar electrosurgery applications, as previously discussed, a surgical instrument having an active electrode and a return electrode can be utilized, wherein the active electrode and the return electrode can be positioned against, or adjacent to, the tissue to be treated such that current can flow from the active electrode to the return electrode through the tissue. Accordingly, the electrosurgical/RF module23 generator may be configured for therapeutic purposes by applying electrical energy to the tissue T sufficient for treating the tissue (e.g., cauterization).

In one embodiment, the electrosurgical/RF generator module23 may be configured to deliver a sub-therapeutic RF signal to implement a tissue impedance measurement module. In one embodiment, the electrosurgical/RF generator module23 comprises a bipolar radio frequency generator as described in more detail below. In one embodiment, the electrosurgical/RF generator module12 may be configured to monitor electrical impedance Z, of tissue T and to control the characteristics of time and power level based on the tissue T by way of a return electrode on provided on a clamp member of theend effector assembly26. Accordingly, the electrosurgical/RF generator module23 may be configured for sub-therapeutic purposes for measuring the impedance or other electrical characteristics of the tissue T. Techniques and circuit configurations for measuring the impedance or other electrical characteristics of tissue T are discussed in more detail in commonly assigned U.S. Patent Publication No. 2011/0015631, entitled ELECTROSURGICAL GENERATOR FOR ULTRASONIC SURGICAL INSTRUMENTS, now U.S. Pat. No. 8,663,220, the disclosure of which is herein incorporated by reference in its entirety.

A suitableultrasonic generator module21 may be configured to functionally operate in a manner similar to the GEN300 sold by Ethicon Endo-Surgery, Inc. of Cincinnati, Ohio as is disclosed in one or more of the following U.S. patents, all of which are incorporated by reference herein: U.S. Pat. No. 6,480,796 (METHOD FOR IMPROVING THE START UP OF AN ULTRASONIC SYSTEM UNDER ZERO LOAD CONDITIONS); U.S. Pat. No. 6,537,291 (METHOD FOR DETECTING BLADE BREAKAGE USING RATE AND/OR IMPEDANCE INFORMATION); U.S. Pat. No. 6,662,127 (METHOD FOR DETECTING PRESENCE OF A BLADE IN AN ULTRASONIC SYSTEM); U.S. Pat. No. 6,679,899 (METHOD FOR DETECTING TRANSVERSE VIBRATIONS IN AN ULTRASONIC HAND PIECE); U.S. Pat. No. 6,977,495 (DETECTION CIRCUITRY FOR SURGICAL HANDPIECE SYSTEM); U.S. Pat. No. 7,077,853 (METHOD FOR CALCULATING TRANSDUCER CAPACITANCE TO DETERMINE TRANSDUCER TEMPERATURE); U.S. Pat. No. 7,179,271 (METHOD FOR DRIVING AN ULTRASONIC SYSTEM TO IMPROVE ACQUISITION OF BLADE RESONANCE FREQUENCY AT STARTUP); and U.S. Pat. No. 7,273,483 (APPARATUS AND METHOD FOR ALERTING GENERATOR FUNCTION IN AN ULTRASONIC SURGICAL SYSTEM).

It will be appreciated that in various embodiments, thegenerator20 may be configured to operate in several modes. In one mode, thegenerator20 may be configured such that theultrasonic generator module21 and the electrosurgical/RF generator module23 may be operated independently.

For example, theultrasonic generator module21 may be activated to apply ultrasonic energy to theend effector assembly26 and subsequently, either therapeutic sub-therapeutic RF energy may be applied to theend effector assembly26 by the electrosurgical/RF generator module23. As previously discussed, the subtherapeutic electrosurgical/RF energy may be applied to tissue clamped between claim elements of theend effector assembly26 to measure tissue impedance to control the activation, or modify the activation, of theultrasonic generator module21. Tissue impedance feedback from the application of the subtherapeutic energy also may be employed to activate a therapeutic level of the electrosurgical/RF generator module23 to seal the tissue (e.g., vessel) clamped between claim elements of theend effector assembly26.

In another embodiment, theultrasonic generator module21 and the electrosurgical/RF generator module23 may be activated simultaneously. In one example, theultrasonic generator module21 is simultaneously activated with a sub-therapeutic RF energy level to measure tissue impedance simultaneously while the ultrasonic blade of theend effector assembly26 cuts and coagulates the tissue (or vessel) clamped between the clamp elements of theend effector assembly26. Such feedback may be employed, for example, to modify the drive output of theultrasonic generator module21. In another example, theultrasonic generator module21 may be driven simultaneously with electrosurgical/RF generator module23 such that the ultrasonic blade portion of theend effector assembly26 is employed for cutting the damaged tissue while the electrosurgical/RF energy is applied to electrode portions of the endeffector clamp assembly26 for sealing the tissue (or vessel).

When thegenerator20 is activated via the triggering mechanism, in one embodiment electrical energy is continuously applied by thegenerator20 to a transducer stack or assembly of the acoustic assembly. In another embodiment, electrical energy is intermittently applied (e.g., pulsed) by thegenerator20. A phase-locked loop in the control system of thegenerator20 may monitor feedback from the acoustic assembly. The phase lock loop adjusts the frequency of the electrical energy sent by thegenerator20 to match the resonant frequency of the selected longitudinal mode of vibration of the acoustic assembly. In addition, a second feedback loop in thecontrol system25 maintains the electrical current supplied to the acoustic assembly at a pre-selected constant level in order to achieve substantially constant excursion at theend effector18 of the acoustic assembly. In yet another embodiment, a third feedback loop in thecontrol system25 monitors impedance between electrodes located in theend effector assembly26. AlthoughFIGS.1-9 show a manually operated ultrasonic surgical instrument, it will be appreciated that ultrasonic surgical instruments may also be used in robotic applications, for example, as described herein, as well as combinations of manual and robotic applications.

In ultrasonic operation mode, the electrical signal supplied to the acoustic assembly may cause the distal end of theend effector18, to vibrate longitudinally in the range of, for example, approximately 20 kHz to 250 kHz. According to various embodiments, theblade22 may vibrate in the range of about 54 kHz to 56 kHz, for example, at about 55.5 kHz. In other embodiments, theblade22 may vibrate at other frequencies including, for example, about 31 kHz or about 80 kHz. The excursion of the vibrations at the blade can be controlled by, for example, controlling the amplitude of the electrical signal applied to the transducer assembly of the acoustic assembly by thegenerator20. As noted above, the triggering mechanism of thegenerator20 allows a user to activate thegenerator20 so that electrical energy may be continuously or intermittently supplied to the acoustic assembly. Thegenerator20 also has a power line for insertion in an electro-surgical unit or conventional electrical outlet. It is contemplated that thegenerator20 can also be powered by a direct current (DC) source, such as a battery. Thegenerator20 can comprise any suitable generator, such as Model No. GEN04, and/or Model No. GEN11 available from Ethicon Endo-Surgery, Inc.

FIG.2 is a left perspective view of one example embodiment of the ultrasonicsurgical instrument10 showing thehandle assembly12, thedistal rotation assembly13, theelongated shaft assembly14, and theend effector assembly26. In the illustrated embodiment theelongated shaft assembly14 comprises adistal end52 dimensioned to mechanically engage theend effector assembly26 and aproximal end50 that mechanically engages thehandle assembly12 and thedistal rotation assembly13. Theproximal end50 of theelongated shaft assembly14 is received within thehandle assembly12 and thedistal rotation assembly13. More details relating to the connections between theelongated shaft assembly14, thehandle assembly12, and thedistal rotation assembly13 are provided in the description ofFIGS.5 and7.

In the illustrated embodiment, thetrigger assembly24 comprises atrigger32 that operates in conjunction with a fixedhandle34. The fixedhandle34 and thetrigger32 are ergonomically formed and adapted to interface comfortably with the user. The fixedhandle34 is integrally associated with thehandle assembly12. Thetrigger32 is pivotally movable relative to the fixedhandle34 as explained in more detail below with respect to the operation of the ultrasonicsurgical instrument10. Thetrigger32 is pivotally movable in direction33A toward the fixedhandle34 when the user applies a squeezing force against thetrigger32. A spring element98 (FIG.5) causes thetrigger32 to pivotally move in direction33B when the user releases the squeezing force against thetrigger32.

In one example embodiment, thetrigger32 comprises anelongated trigger hook36, which defines anaperture38 between theelongated trigger hook36 and thetrigger32. Theaperture38 is suitably sized to receive one or multiple fingers of the user therethrough. Thetrigger32 also may comprise aresilient portion32amolded over thetrigger32 substrate. The overmoldedresilient portion32ais formed to provide a more comfortable contact surface for control of thetrigger32 in outward direction33B. In one example embodiment, the overmoldedresilient portion32amay be provided over a portion of theelongated trigger hook36. The proximal surface of theelongated trigger hook32 remains uncoated or coated with a non-resilient substrate to enable the user to easily slide their fingers in and out of theaperture38. In another embodiment, the geometry of the trigger forms a fully closed loop which defines an aperture suitably sized to receive one or multiple fingers of the user therethrough. The fully closed loop trigger also may comprise a resilient portion molded over the trigger substrate.

In one example embodiment, the fixedhandle34 comprises aproximal contact surface40 and a grip anchor orsaddle surface42. Thesaddle surface42 rests on the web where the thumb and the index finger are joined on the hand. Theproximal contact surface40 has a pistol grip contour that receives the palm of the hand in a normal pistol grip with no rings or apertures. The profile curve of theproximal contact surface40 may be contoured to accommodate or receive the palm of the hand. Astabilization tail44 is located towards a more proximal portion of thehandle assembly12. Thestabilization tail44 may be in contact with the uppermost web portion of the hand located between the thumb and the index finger to stabilize thehandle assembly12 and make thehandle assembly12 more controllable.

In one example embodiment, theswitch assembly28 may comprise atoggle switch30. Thetoggle switch30 may be implemented as a single component with a central pivot304 located within inside thehandle assembly12 to eliminate the possibility of simultaneous activation. In one example embodiment, thetoggle switch30 comprises a first projectingknob30aand a second projectingknob30bto set the power setting of theultrasonic transducer16 between a minimum power level (e.g., MIN) and a maximum power level (e.g., MAX). In another embodiment, the rocker switch may pivot between a standard setting and a special setting. The special setting may allow one or more special programs to be implemented by the device. Thetoggle switch30 rotates about the central pivot as the first projectingknob30aand the second projectingknob30bare actuated. The one or more projectingknobs30a,30bare coupled to one or more arms that move through a small arc and cause electrical contacts to close or open an electric circuit to electrically energize or de-energize theultrasonic transducer16 in accordance with the activation of the first or second projectingknobs30a,30b. Thetoggle switch30 is coupled to thegenerator20 to control the activation of theultrasonic transducer16. Thetoggle switch30 comprises one or more electrical power setting switches to activate theultrasonic transducer16 to set one or more power settings for theultrasonic transducer16. The forces required to activate thetoggle switch30 are directed substantially toward thesaddle point42, thus avoiding any tendency of the instrument to rotate in the hand when thetoggle switch30 is activated.

In one example embodiment, the first and second projectingknobs30a,30bare located on the distal end of thehandle assembly12 such that they can be easily accessible by the user to activate the power with minimal, or substantially no, repositioning of the hand grip, making it suitable to maintain control and keep attention focused on the surgical site (e.g., a monitor in a laparoscopic procedure) while activating thetoggle switch30. The projecting knobs30a,30bmay be configured to wrap around the side of thehandle assembly12 to some extent to be more easily accessible by variable finger lengths and to allow greater freedom of access to activation in awkward positions or for shorter fingers.

In the illustrated embodiment, the first projectingknob30acomprises a plurality oftactile elements30c, e.g., textured projections or “bumps” in the illustrated embodiment, to allow the user to differentiate the first projectingknob30afrom the second projectingknob30b. It will be appreciated by those skilled in the art that several ergonomic features may be incorporated into thehandle assembly12. Such ergonomic features are described in U.S. Patent Application Publication No. 2009/0105750 entitled ERGONOMIC SURGICAL INSTRUMENTS, now U.S. Pat. No. 8,623,027, which is incorporated by reference herein in its entirety.

In one example embodiment, thetoggle switch30 may be operated by the hand of the user. The user may easily access the first and second projectingknobs30a,30bat any point while also avoiding inadvertent or unintentional activation at any time. Thetoggle switch30 may readily operated with a finger to control the power to theultrasonic assembly16 and/or to theultrasonic assembly16. For example, the index finger may be employed to activate thefirst contact portion30ato turn on theultrasonic assembly16 to a maximum (MAX) power level. The index finger may be employed to activate thesecond contact portion30bto turn on theultrasonic assembly16 to a minimum (MIN) power level. In another embodiment, the rocker switch may pivot theinstrument10 between a standard setting and a special setting. The special setting may allow one or more special programs to be implemented by theinstrument10. Thetoggle switch30 may be operated without the user having to look at the first or second projectingknob30a,30b. For example, the first projectingknob30aor the second projectingknob30bmay comprise a texture or projections to tactilely differentiate between the first and second projectingknobs30a,30bwithout looking.

In other embodiments, thetrigger32 and/or thetoggle switch30 may be employed to actuate the electrosurgical/RF generator module23 individually or in combination with activation of theultrasonic generator module21.

In one example embodiment, thedistal rotation assembly13 is rotatable without limitation in either direction about a longitudinal axis “T.” Thedistal rotation assembly13 is mechanically engaged to theelongated shaft assembly14. Thedistal rotation assembly13 is located on a distal end of thehandle assembly12. Thedistal rotation assembly13 comprises acylindrical hub46 and arotation knob48 formed over thehub46. Thehub46 mechanically engages theelongated shaft assembly14. Therotation knob48 may comprise fluted polymeric features and may be engaged by a finger (e.g., an index finger) to rotate theelongated shaft assembly14. Thehub46 may comprise a material molded over the primary structure to form therotation knob48. Therotation knob48 may be overmolded over thehub46. Thehub46 comprises an end cap portion46athat is exposed at the distal end. The end cap portion46aof thehub46 may contact the surface of a trocar during laparoscopic procedures. Thehub46 may be formed of a hard durable plastic such as polycarbonate to alleviate any friction that may occur between the end cap portion46aand the trocar. Therotation knob48 may comprise “scallops” or flutes formed of raisedribs48aandconcave portions48blocated between theribs48ato provide a more precise rotational grip. In one example embodiment, therotation knob48 may comprise a plurality of flutes (e.g., three or more flutes). In other embodiments, any suitable number of flutes may be employed. Therotation knob48 may be formed of a softer polymeric material overmolded onto the hard plastic material. For example, therotation knob48 may be formed of pliable, resilient, flexible polymeric materials including Versaflex® TPE alloys made by GLS Corporation, for example. This softer overmolded material may provide a greater grip and more precise control of the movement of therotation knob48. It will be appreciated that any materials that provide adequate resistance to sterilization, are biocompatible, and provide adequate frictional resistance to surgical gloves may be employed to form therotation knob48.

In one example embodiment, thehandle assembly12 is formed from two (2) housing portions or shrouds comprising afirst portion12aand asecond portion12b. From the perspective of a user viewing thehandle assembly12 from the distal end towards the proximal end, thefirst portion12ais considered the right portion and thesecond portion12bis considered the left portion. Each of the first andsecond portions12a,12bincludes a plurality of interfaces69 (FIG.5) dimensioned to mechanically align and engage each another to form thehandle assembly12 and enclosing the internal working components thereof. The fixedhandle34, which is integrally associated with thehandle assembly12, takes shape upon the assembly of the first andsecond portions12aand12bof thehandle assembly12. A plurality of additional interfaces (not shown) may be disposed at various points around the periphery of the first andsecond portions12aand12bof thehandle assembly12 for ultrasonic welding purposes, e.g., energy direction/deflection points. The first andsecond portions12aand12b(as well as the other components described below) may be assembled together in any fashion known in the art. For example, alignment pins, snap-like interfaces, tongue and groove interfaces, locking tabs, adhesive ports, may all be utilized either alone or in combination for assembly purposes.

In one example embodiment, theelongated shaft assembly14 comprises aproximal end50 adapted to mechanically engage thehandle assembly12 and thedistal rotation assembly13; and adistal end52 adapted to mechanically engage theend effector assembly26. Theelongated shaft assembly14 comprises an outertubular sheath56 and a reciprocating tubular actuatingmember58 located within the outertubular sheath56. The proximal end of the tubular reciprocatingtubular actuating member58 is mechanically engaged to thetrigger32 of thehandle assembly12 to move in either direction60A or60B in response to the actuation and/or release of thetrigger32. The pivotablymoveable trigger32 may generate reciprocating motion along the longitudinal axis “T.” Such motion may be used, for example, to actuate the jaws or clamping mechanism of theend effector assembly26. A series of linkages translate the pivotal rotation of thetrigger32 to axial movement of a yoke coupled to an actuation mechanism, which controls the opening and closing of the jaws of the clamping mechanism of theend effector assembly26. The distal end of the tubular reciprocatingtubular actuating member58 is mechanically engaged to theend effector assembly26. In the illustrated embodiment, the distal end of the tubular reciprocatingtubular actuating member58 is mechanically engaged to aclamp arm assembly64, which is pivotable about apivot point70, to open and close theclamp arm assembly64 in response to the actuation and/or release of thetrigger32. For example, in the illustrated embodiment, theclamp arm assembly64 is movable in direction62A from an open position to a closed position about apivot point70 when thetrigger32 is squeezed in direction33A. Theclamp arm assembly64 is movable in direction62B from a closed position to an open position about thepivot point70 when thetrigger32 is released or outwardly contacted in direction33B.

In one example embodiment, theend effector assembly26 is attached at thedistal end52 of theelongated shaft assembly14 and includes aclamp arm assembly64 and ablade66. The jaws of the clamping mechanism of theend effector assembly26 are formed byclamp arm assembly64 and theblade66. Theblade66 is ultrasonically actuatable and is acoustically coupled to theultrasonic transducer16. Thetrigger32 on thehandle assembly12 is ultimately connected to a drive assembly, which together, mechanically cooperate to effect movement of theclamp arm assembly64. Squeezing thetrigger32 in direction33A moves theclamp arm assembly64 in direction62A from an open position, wherein theclamp arm assembly64 and theblade66 are disposed in a spaced relation relative to one another, to a clamped or closed position, wherein theclamp arm assembly64 and theblade66 cooperate to grasp tissue therebetween. Theclamp arm assembly64 may comprise aclamp pad69 to engage tissue between theblade66 and theclamp arm64. Releasing thetrigger32 in direction33B moves theclamp arm assembly64 in direction62B from a closed relationship, to an open position, wherein theclamp arm assembly64 and theblade66 are disposed in a spaced relation relative to one another.

The proximal portion of thehandle assembly12 comprises aproximal opening68 to receive the distal end of theultrasonic assembly16. Theultrasonic assembly16 is inserted in theproximal opening68 and is mechanically engaged to theelongated shaft assembly14.

In one example embodiment, theelongated trigger hook36 portion of thetrigger32 provides a longer trigger lever with a shorter span and rotation travel. The longer lever of theelongated trigger hook36 allows the user to employ multiple fingers within theaperture38 to operate theelongated trigger hook36 and cause thetrigger32 to pivot in direction33B to open the jaws of theend effector assembly26. For example, the user may insert three fingers (e.g., the middle, ring, and little fingers) in theaperture38. Multiple fingers allows the surgeon to exert higher input forces on thetrigger32 and theelongated trigger hook36 to activate theend effector assembly26. The shorter span and rotation travel creates a more comfortable grip when closing or squeezing thetrigger32 in direction33A or when opening thetrigger32 in the outward opening motion in direction33B lessening the need to extend the fingers further outward. This substantially lessens hand fatigue and strain associated with the outward opening motion of thetrigger32 in direction33B. The outward opening motion of the trigger may be spring-assisted by spring element98 (FIG.5) to help alleviate fatigue. The opening spring force is sufficient to assist the ease of opening, but not strong enough to adversely impact the tactile feedback of tissue tension during spreading dissection.

For example, during a surgical procedure either the index finger may be used to control the rotation of theelongated shaft assembly14 to locate the jaws of theend effector assembly26 in a suitable orientation. The middle and/or the other lower fingers may be used to squeeze thetrigger32 and grasp tissue within the jaws. Once the jaws are located in the desired position and the jaws are clamped against the tissue, the index finger can be used to activate thetoggle switch30 to adjust the power level of theultrasonic transducer16 to treat the tissue. Once the tissue has been treated, the user the may release thetrigger32 by pushing outwardly in the distal direction against theelongated trigger hook36 with the middle and/or lower fingers to open the jaws of theend effector assembly26. This basic procedure may be performed without the user having to adjust their grip of thehandle assembly12.

FIGS.3-4 illustrate the connection of theelongated shaft assembly14 relative to theend effector assembly26. As previously described, in the illustrated embodiment, theend effector assembly26 comprises aclamp arm assembly64 and ablade66 to form the jaws of the clamping mechanism. Theblade66 may be an ultrasonically actuatable blade acoustically coupled to theultrasonic transducer16. Thetrigger32 is mechanically connected to a drive assembly. Together, thetrigger32 and the drive assembly mechanically cooperate to move theclamp arm assembly64 to an open position in direction62A wherein theclamp arm assembly64 and theblade66 are disposed in spaced relation relative to one another, to a clamped or closed position in direction62B wherein theclamp arm assembly64 and theblade66 cooperate to grasp tissue therebetween. Theclamp arm assembly64 may comprise aclamp pad69 to engage tissue between theblade66 and theclamp arm64. The distal end of the tubular reciprocatingtubular actuating member58 is mechanically engaged to theend effector assembly26. In the illustrated embodiment, the distal end of the tubular reciprocatingtubular actuating member58 is mechanically engaged to theclamp arm assembly64, which is pivotable about thepivot point70, to open and close theclamp arm assembly64 in response to the actuation and/or release of thetrigger32. For example, in the illustrated embodiment, theclamp arm assembly64 is movable from an open position to a closed position in direction62B about apivot point70 when thetrigger32 is squeezed in direction33A. Theclamp arm assembly64 is movable from a closed position to an open position in direction62A about thepivot point70 when thetrigger32 is released or outwardly contacted in direction33B.

As previously discussed, theclamp arm assembly64 may comprise electrodes electrically coupled to the electrosurgical/RF generator module23 to receive therapeutic and/or sub-therapeutic energy, where the electrosurgical/RF energy may be applied to the electrodes either simultaneously or non-simultaneously with the ultrasonic energy being applied to theblade66. Such energy activations may be applied in any suitable combinations to achieve a desired tissue effect in cooperation with an algorithm or other control logic.

FIG.5 is an exploded view of the ultrasonicsurgical instrument10 shown inFIG.2. In the illustrated embodiment, the exploded view shows the internal elements of thehandle assembly12, thehandle assembly12, thedistal rotation assembly13, theswitch assembly28, and theelongated shaft assembly14. In the illustrated embodiment, the first andsecond portions12a,12bmate to form thehandle assembly12. The first andsecond portions12a,12beach comprises a plurality ofinterfaces69 dimensioned to mechanically align and engage one another to form thehandle assembly12 and enclose the internal working components of the ultrasonicsurgical instrument10. Therotation knob48 is mechanically engaged to the outertubular sheath56 so that it may be rotated incircular direction54 up to 360°. The outertubular sheath56 is located over the reciprocating tubular actuatingmember58, which is mechanically engaged to and retained within thehandle assembly12 via a plurality ofcoupling elements72. Thecoupling elements72 may comprise an O-ring72a, a tube collar cap72b, a distal washer72c, aproximal washer72d, and athread tube collar72e. The reciprocating tubular actuatingmember58 is located within areciprocating yoke84, which is retained between the first andsecond portions12a,12bof thehandle assembly12. Theyoke84 is part of areciprocating yoke assembly88. A series of linkages translate the pivotal rotation of theelongated trigger hook32 to the axial movement of thereciprocating yoke84, which controls the opening and closing of the jaws of the clamping mechanism of theend effector assembly26 at the distal end of the ultrasonicsurgical instrument10. In one example embodiment, a four-link design provides mechanical advantage in a relatively short rotation span, for example.

In one example embodiment, anultrasonic transmission waveguide78 is disposed inside the reciprocating tubular actuatingmember58. Thedistal end52 of theultrasonic transmission waveguide78 is acoustically coupled (e.g., directly or indirectly mechanically coupled) to theblade66 and theproximal end50 of theultrasonic transmission waveguide78 is received within thehandle assembly12. Theproximal end50 of theultrasonic transmission waveguide78 is adapted to acoustically couple to the distal end of theultrasonic transducer16 as discussed in more detail below. Theultrasonic transmission waveguide78 is isolated from the other elements of theelongated shaft assembly14 by aprotective sheath80 and a plurality ofisolation elements82, such as silicone rings. The outertubular sheath56, the reciprocating tubular actuatingmember58, and theultrasonic transmission waveguide78 are mechanically engaged by apin74. Theswitch assembly28 comprises thetoggle switch30 andelectrical elements86a,bto electrically energize theultrasonic transducer16 in accordance with the activation of the first or second projectingknobs30a,30b.

In one example embodiment, the outertubular sheath56 isolates the user or the patient from the ultrasonic vibrations of theultrasonic transmission waveguide78. The outertubular sheath56 generally includes ahub76. The outertubular sheath56 is threaded onto the distal end of thehandle assembly12. Theultrasonic transmission waveguide78 extends through the opening of the outertubular sheath56 and theisolation elements82 isolate theultrasonic transmission waveguide24 from the outertubular sheath56. The outertubular sheath56 may be attached to thewaveguide78 with thepin74. The hole to receive thepin74 in thewaveguide78 may occur nominally at a displacement node. Thewaveguide78 may screw or snap into the hand piece handleassembly12 by a stud. Flat portions on thehub76 may allow the assembly to be torqued to a required level. In one example embodiment, thehub76 portion of the outertubular sheath56 is preferably constructed from plastic and the tubular elongated portion of the outertubular sheath56 is fabricated from stainless steel. Alternatively, theultrasonic transmission waveguide78 may comprise polymeric material surrounding it to isolate it from outside contact.

In one example embodiment, the distal end of theultrasonic transmission waveguide78 may be coupled to the proximal end of theblade66 by an internal threaded connection, preferably at or near an antinode. It is contemplated that theblade66 may be attached to theultrasonic transmission waveguide78 by any suitable means, such as a welded joint or the like. Although theblade66 may be detachable from theultrasonic transmission waveguide78, it is also contemplated that the single element end effector (e.g., the blade66) and theultrasonic transmission waveguide78 may be formed as a single unitary piece.

In one example embodiment, thetrigger32 is coupled to a linkage mechanism to translate the rotational motion of thetrigger32 in directions33A and33B to the linear motion of the reciprocating tubular actuatingmember58 in corresponding directions60A and60B. Thetrigger32 comprises a first set offlanges98 with openings formed therein to receive afirst yoke pin92a. Thefirst yoke pin92ais also located through a set of openings formed at the distal end of theyoke84. Thetrigger32 also comprises a second set offlanges96 to receive afirst end92aof alink92. Atrigger pin90 is received in openings formed in thelink92 and the second set offlanges96. Thetrigger pin90 is received in the openings formed in thelink92 and the second set offlanges96 and is adapted to couple to the first andsecond portions12a,12bof thehandle assembly12 to form a trigger pivot point for thetrigger32. Asecond end92bof thelink92 is received in a slot384 formed in a proximal end of theyoke84 and is retained therein by asecond yoke pin94b. As thetrigger32 is pivotally rotated about thepivot point190 formed by thetrigger pin90, the yoke translates horizontally along longitudinal axis “T” in a direction indicated by arrows60A,B.

FIG.8 illustrates one example embodiment of an ultrasonicsurgical instrument10. In the illustrated embodiment, a cross-sectional view of theultrasonic transducer16 is shown within a partial cutaway view of thehandle assembly12. One example embodiment of the ultrasonicsurgical instrument10 comprises theultrasonic signal generator20 coupled to theultrasonic transducer16, comprising ahand piece housing99, and an ultrasonically actuatable single or multiple elementend effector assembly26. As previously discussed, theend effector assembly26 comprises theultrasonically actuatable blade66 and theclamp arm64. Theultrasonic transducer16, which is known as a “Langevin stack”, generally includes atransduction portion100, a first resonator portion or end-bell102, and a second resonator portion or fore-bell104, and ancillary components. The total construction of these components is a resonator. Theultrasonic transducer16 is preferably an integral number of one-half system wavelengths (nλ/2; where “n” is any positive integer; e.g., n=1, 2, 3 . . . ) in length as will be described in more detail later. Anacoustic assembly106 includes theultrasonic transducer16, anose cone108, avelocity transformer118, and asurface110.

In one example embodiment, the distal end of the end-bell102 is connected to the proximal end of thetransduction portion100, and the proximal end of the fore-bell104 is connected to the distal end of thetransduction portion100. The fore-bell104 and the end-bell102 have a length determined by a number of variables, including the thickness of thetransduction portion100, the density and modulus of elasticity of the material used to manufacture the end-bell102 and the fore-bell22, and the resonant frequency of theultrasonic transducer16. The fore-bell104 may be tapered inwardly from its proximal end to its distal end to amplify the ultrasonic vibration amplitude as thevelocity transformer118, or alternately may have no amplification. A suitable vibrational frequency range may be about 20 Hz to 32 kHz and a well-suited vibrational frequency range may be about 30-10 kHz. A suitable operational vibrational frequency may be approximately 55.5 kHz, for example.

In one example embodiment, thepiezoelectric elements112 may be fabricated from any suitable material, such as, for example, lead zirconate-titanate, lead meta-niobate, lead titanate, barium titanate, or other piezoelectric ceramic material. Each ofpositive electrodes114, negative electrodes116, and thepiezoelectric elements112 has a bore extending through the center. The positive andnegative electrodes114 and116 are electrically coupled towires120 and122, respectively. Thewires120 and122 are encased within thecable22 and electrically connectable to theultrasonic signal generator20.

Theultrasonic transducer16 of theacoustic assembly106 converts the electrical signal from theultrasonic signal generator20 into mechanical energy that results in primarily a standing acoustic wave of longitudinal vibratory motion of theultrasonic transducer16 and theblade66 portion of theend effector assembly26 at ultrasonic frequencies. In another embodiment, the vibratory motion of the ultrasonic transducer may act in a different direction. For example, the vibratory motion may comprise a local longitudinal component of a more complicated motion of the tip of theelongated shaft assembly14. A suitable generator is available as model number GEN11, from Ethicon Endo-Surgery, Inc., Cincinnati, Ohio. When theacoustic assembly106 is energized, a vibratory motion standing wave is generated through theacoustic assembly106. The ultrasonicsurgical instrument10 is designed to operate at a resonance such that an acoustic standing wave pattern of predetermined amplitude is produced. The amplitude of the vibratory motion at any point along theacoustic assembly106 depends upon the location along theacoustic assembly106 at which the vibratory motion is measured. A minimum or zero crossing in the vibratory motion standing wave is generally referred to as a node (i.e., where motion is minimal), and a local absolute value maximum or peak in the standing wave is generally referred to as an anti-node (e.g., where local motion is maximal). The distance between an anti-node and its nearest node is one-quarter wavelength (λ/4).

Thewires120 and122 transmit an electrical signal from theultrasonic signal generator20 to thepositive electrodes114 and the negative electrodes116. Thepiezoelectric elements112 are energized by the electrical signal supplied from theultrasonic signal generator20 in response to an actuator224, such as a foot switch, for example, to produce an acoustic standing wave in theacoustic assembly106. The electrical signal causes disturbances in thepiezoelectric elements112 in the form of repeated small displacements resulting in large alternating compression and tension forces within the material. The repeated small displacements cause thepiezoelectric elements112 to expand and contract in a continuous manner along the axis of the voltage gradient, producing longitudinal waves of ultrasonic energy. The ultrasonic energy is transmitted through theacoustic assembly106 to theblade66 portion of theend effector assembly26 via a transmission component or an ultrasonictransmission waveguide portion78 of theelongated shaft assembly14.

In one example embodiment, in order for theacoustic assembly106 to deliver energy to theblade66 portion of theend effector assembly26, all components of theacoustic assembly106 must be acoustically coupled to theblade66. The distal end of theultrasonic transducer16 may be acoustically coupled at thesurface110 to the proximal end of theultrasonic transmission waveguide78 by a threaded connection such as astud124.

In one example embodiment, the components of theacoustic assembly106 are preferably acoustically tuned such that the length of any assembly is an integral number of one-half wavelengths (nλ/2), where the wavelength λ is the wavelength of a pre-selected or operating longitudinal vibration drive frequency fa of theacoustic assembly106. It is also contemplated that theacoustic assembly106 may incorporate any suitable arrangement of acoustic elements.

In one example embodiment, theblade66 may have a length substantially equal to an integral multiple of one-half system wavelengths (nλ/2). A distal end of theblade66 may be disposed near an antinode in order to provide the maximum longitudinal excursion of the distal end. When the transducer assembly is energized, the distal end of theblade66 may be configured to move in the range of, for example, approximately 10 to 500 microns peak-to-peak, and preferably in the range of about 30 to 64 microns at a predetermined vibrational frequency of 55 kHz, for example.

In one example embodiment, theblade66 may be coupled to theultrasonic transmission waveguide78. Theblade66 and theultrasonic transmission waveguide78 as illustrated are formed as a single unit construction from a material suitable for transmission of ultrasonic energy. Examples of such materials include Ti6A14V (an alloy of Titanium including Aluminum and Vanadium), Aluminum, Stainless Steel, or other suitable materials. Alternately, theblade66 may be separable (and of differing composition) from theultrasonic transmission waveguide78, and coupled by, for example, a stud, weld, glue, quick connect, or other suitable known methods. The length of theultrasonic transmission waveguide78 may be substantially equal to an integral number of one-half wavelengths (nλ/2), for example. Theultrasonic transmission waveguide78 may be preferably fabricated from a solid core shaft constructed out of material suitable to propagate ultrasonic energy efficiently, such as the titanium alloy discussed above (i.e., Ti6A14V) or any suitable aluminum alloy, or other alloys, for example.

In one example embodiment, theultrasonic transmission waveguide78 comprises a longitudinally projecting attachment post at a proximal end to couple to thesurface110 of theultrasonic transmission waveguide78 by a threaded connection such as thestud124. Theultrasonic transmission waveguide78 may include a plurality of stabilizing silicone rings or compliant supports82 (FIG.5) positioned at a plurality of nodes. The silicone rings82 dampen undesirable vibration and isolate the ultrasonic energy from an outer protective sheath80 (FIG.5) assuring the flow of ultrasonic energy in a longitudinal direction to the distal end of theblade66 with maximum efficiency.

FIG.9 illustrates one example embodiment of theproximal rotation assembly128. In the illustrated embodiment, theproximal rotation assembly128 comprises theproximal rotation knob134 inserted over thecylindrical hub135. Theproximal rotation knob134 comprises a plurality ofradial projections138 that are received in correspondingslots130 formed on a proximal end of thecylindrical hub135. Theproximal rotation knob134 defines an opening142 to receive the distal end of theultrasonic transducer16. Theradial projections138 are formed of a soft polymeric material and define a diameter that is undersized relative to the outside diameter of theultrasonic transducer16 to create a friction interference fit when the distal end of theultrasonic transducer16. The polymericradial projections138 protrude radially into the opening142 to form “gripper” ribs that firmly grip the exterior housing of theultrasonic transducer16. Therefore, theproximal rotation knob134 securely grips theultrasonic transducer16.

The distal end of thecylindrical hub135 comprises acircumferential lip132 and acircumferential bearing surface140. The circumferential lip engages a groove formed in thehousing12 and thecircumferential bearing surface140 engages thehousing12. Thus, thecylindrical hub135 is mechanically retained within the two housing portions (not shown) of thehousing12. Thecircumferential lip132 of thecylindrical hub135 is located or “trapped” between the first andsecond housing portions12a,12band is free to rotate in place within the groove. Thecircumferential bearing surface140 bears against interior portions of the housing to assist proper rotation. Thus, thecylindrical hub135 is free to rotate in place within the housing. The user engages theflutes136 formed on theproximal rotation knob134 with either the finger or the thumb to rotate thecylindrical hub135 within thehousing12.

In one example embodiment, thecylindrical hub135 may be formed of a durable plastic such as polycarbonate. In one example embodiment, thecylindrical hub135 may be formed of a siliconized polycarbonate material. In one example embodiment, theproximal rotation knob134 may be formed of pliable, resilient, flexible polymeric materials including Versaflex® TPE alloys made by GLS Corporation, for example. Theproximal rotation knob134 may be formed of elastomeric materials, thermoplastic rubber known as Santoprene®, other thermoplastic vulcanizates (TPVs), or elastomers, for example. The embodiments, however, are not limited in this context.

FIG.10 illustrates one example embodiment of asurgical system200 including asurgical instrument210 having singleelement end effector278. Thesystem200 may include atransducer assembly216 coupled to theend effector278 and asheath256 positioned around the proximal portions of theend effector278 as shown. Thetransducer assembly216 andend effector278 may operate in a manner similar to that of thetransducer assembly16 andend effector18 described above to produce ultrasonic energy that may be transmitted to tissue viablade226′

FIGS.11-18C illustrate various embodiments of surgical instruments that utilize therapeutic and/or subtherapeutic electrical energy to treat and/or destroy tissue or provide feedback to the generators (e.g., electrosurgical instruments). The embodiments ofFIGS.11-18C are adapted for use in a manual or hand-operated manner, although electrosurgical instruments may be utilized in robotic applications as well.FIG.11 is a perspective view of one example embodiment of asurgical instrument system300 comprising an electrical energysurgical instrument310. Theelectrosurgical instrument310 may comprise aproximal handle312, a distal working end orend effector326 and an introducer orelongated shaft314 disposed in-between.

Theelectrosurgical system300 can be configured to supply energy, such as electrical energy, ultrasonic energy, heat energy or any combination thereof, to the tissue of a patient either independently or simultaneously as described, for example, in connection withFIG.1, for example. In one example embodiment, theelectrosurgical system300 includes agenerator320 in electrical communication with theelectrosurgical instrument310. Thegenerator320 is connected toelectrosurgical instrument310 via a suitable transmission medium such as acable322. In one example embodiment, thegenerator320 is coupled to a controller, such as acontrol unit325, for example. In various embodiments, thecontrol unit325 may be formed integrally with thegenerator320 or may be provided as a separate circuit module or device electrically coupled to the generator320 (shown in phantom to illustrate this option). Although in the presently disclosed embodiment, thegenerator320 is shown separate from theelectrosurgical instrument310, in one example embodiment, the generator320 (and/or the control unit325) may be formed integrally with theelectrosurgical instrument310 to form aunitary electrosurgical system300, where a battery located within theelectrosurgical instrument310 is the energy source and a circuit coupled to the battery produces the suitable electrical energy, ultrasonic energy, or heat energy. One such example is described herein below in connection withFIGS.17-18C.

Thegenerator320 may comprise an input device335 located on a front panel of thegenerator320 console. The input device335 may comprise any suitable device that generates signals suitable for programming the operation of thegenerator320, such as a keyboard, or input port, for example. In one example embodiment, various electrodes in the first jaw364A and the second jaw364B may be coupled to thegenerator320. Thecable322 may comprise multiple electrical conductors for the application of electrical energy to positive (+) and negative (−) electrodes of theelectrosurgical instrument310. Thecontrol unit325 may be used to activate thegenerator320, which may serve as an electrical source. In various embodiments, thegenerator320 may comprise an RF source, an ultrasonic source, a direct current source, and/or any other suitable type of electrical energy source, for example, which may be activated independently or simultaneously

In various embodiments, theelectrosurgical system300 may comprise at least onesupply conductor331 and at least onereturn conductor333, wherein current can be supplied toelectrosurgical instrument300 via thesupply conductor331 and wherein the current can flow back to thegenerator320 via thereturn conductor333. In various embodiments, thesupply conductor331 and thereturn conductor333 may comprise insulated wires and/or any other suitable type of conductor. In certain embodiments, as described below, thesupply conductor331 and thereturn conductor333 may be contained within and/or may comprise thecable322 extending between, or at least partially between, thegenerator320 and theend effector326 of theelectrosurgical instrument310. In any event, thegenerator320 can be configured to apply a sufficient voltage differential between thesupply conductor331 and thereturn conductor333 such that sufficient current can be supplied to theend effector110.

FIG.12 is a side view of one example embodiment of thehandle312 of thesurgical instrument310. InFIG.12, thehandle312 is shown with half of a first handle body312A (seeFIG.11) removed to illustrate various components within second handle body312B. Thehandle312 may comprise a lever arm321 (e.g., a trigger) which may be pulled along apath33. Thelever arm321 may be coupled to an axially moveable member378 (FIGS.13-16) disposed withinelongated shaft314 by a shuttle384 operably engaged to an extension398 oflever arm321. The shuttle384 may further be connected to a biasing device, such as a spring388, which may also be connected to the second handle body312B, to bias the shuttle384 and thus the axiallymoveable member378 in a proximal direction, thereby urging the jaws364A and364B to an open position as seen inFIG.11. Also, referring toFIGS.11-12, a locking member190 (seeFIG.12) may be moved by a locking switch328 (seeFIG.11) between a locked position, where the shuttle384 is substantially prevented from moving distally as illustrated, and an unlocked position, where the shuttle384 may be allowed to freely move in the distal direction, toward theelongated shaft314. Thehandle312 can be any type of pistol-grip or other type of handle known in the art that is configured to carry actuator levers, triggers or sliders for actuating the first jaw364A and the second jaw364B. Theelongated shaft314 may have a cylindrical or rectangular cross-section, for example, and can comprise a thin-wall tubular sleeve that extends fromhandle312. Theelongated shaft314 may include a bore extending therethrough for carrying actuator mechanisms, for example, the axiallymoveable member378, for actuating the jaws and for carrying electrical leads for delivery of electrical energy to electrosurgical components of theend effector326.

Theend effector326 may be adapted for capturing and transecting tissue and for the contemporaneously welding the captured tissue with controlled application of energy (e.g., RF energy). The first jaw364A and the second jaw364B may close to thereby capture or engage tissue about a longitudinal axis “T” defined by the axiallymoveable member378. The first jaw364A and second jaw364B may also apply compression to the tissue. In some embodiments, theelongated shaft314, along with first jaw364A and second jaw364B, can be rotated a full 360° degrees, as shown by arrow196 (seeFIG.11), relative to handle312. For example, arotation knob348 may be rotatable about the longitudinal axis of theshaft314 and may be coupled to theshaft314 such that rotation of theknob348 causes corresponding rotation of theshaft314. The first jaw364A and the second jaw364B can remain openable and/or closeable while rotated.

FIG.13 shows a perspective view of one example embodiment of theend effector326 with the jaws364A,364B open, whileFIG.14 shows a perspective view of one example embodiment of theend effector326 with the jaws364A,364B closed. As noted above, theend effector326 may comprise the upper first jaw364A and the lower second jaw364B, which may be straight or curved. The first jaw364A and the second jaw364B may each comprise an elongated slot or channel362A and362B, respectively, disposed outwardly along their respective middle portions. Further, the first jaw364A and second jaw364B may each have tissue-gripping elements, such asteeth363, disposed on the inner portions of first jaw364A and second jaw364B. The first jaw364A may comprise an upper first jaw body200A with an upper first outward-facing surface202A and an upper first energy delivery surface365A. The second jaw364B may comprise a lower second jaw body200B with a lower second outward-facing surface202B and a lower second energy delivery surface365B. The first energy delivery surface365A and the second energy delivery surface365B may both extend in a “U” shape about the distal end of theend effector326.

Thelever arm321 of the handle312 (FIG.12) may be adapted to actuate the axiallymoveable member378, which may also function as a jaw-closing mechanism. For example, the axiallymoveable member378 may be urged distally as thelever arm321 is pulled proximally along thepath33 via the shuttle384, as shown inFIG.12 and discussed above.FIG.15 is a perspective view of one example embodiment of the axiallymoveable member378 of thesurgical instrument310. The axiallymoveable member378 may comprise one or several pieces, but in any event, may be movable or translatable with respect to theelongated shaft314 and/or the jaws364A,364B. Also, in at least one example embodiment, the axiallymoveable member378 may be made of17-4 precipitation hardened stainless steel. The distal end of axiallymoveable member378 may comprise a flanged “I”-beam configured to slide within the channels362A and362B in jaws364A and364B. The axiallymoveable member378 may slide within the channels362A,362B to open and close the first jaw364A and the second jaw364B. The distal end of the axiallymoveable member378 may also comprise an upper flange or “c”-shaped portion378A and a lower flange or “c”-shaped portion378B. The flanges378A and378B respectively define inner cam surfaces367A and367B for engaging outward facing surfaces of the first jaw364A and the second jaw364B. The opening-closing of jaws364A and364B can apply very high compressive forces on tissue using cam mechanisms which may include movable “I-beam” axiallymoveable member378 and the outward facing surfaces369A,369B of jaws364A,364B.

More specifically, referring now toFIGS.13-15, collectively, the inner cam surfaces367A and367B of the distal end of axiallymoveable member378 may be adapted to slidably engage the first outward-facing surface369A and the second outward-facing surface369B of the first jaw364A and the second jaw364B, respectively. The channel362A within first jaw364A and the channel362B within the second jaw364B may be sized and configured to accommodate the movement of the axiallymoveable member378, which may comprise a tissue-cuttingelement371, for example, comprising a sharp distal edge.FIG.14, for example, shows the distal end of the axiallymoveable member378 advanced at least partially through channels362A and362B (FIG.13). The advancement of the axiallymoveable member378 may close theend effector326 from the open configuration shown inFIG.13. In the closed position shown byFIG.14, the upper first jaw364A and lower second jaw364B define a gap or dimension D between the first energy delivery surface365A and second energy delivery surface365B of first jaw364A and second jaw364B, respectively. In various embodiments, dimension D can equal from about 0.0005″ to about 0.040″, for example, and in some embodiments, between about 0.001″ to about 0.010″, for example. Also, the edges of the first energy delivery surface365A and the second energy delivery surface365B may be rounded to prevent the dissection of tissue.

FIG.16 is a section view of one example embodiment of theend effector326 of thesurgical instrument310. The engagement, or tissue-contacting, surface365B of the lower jaw364B is adapted to deliver energy to tissue, at least in part, through a conductive-resistive matrix, such as a variable resistive positive temperature coefficient (PTC) body, as discussed in more detail below. At least one of the upper and lower jaws364A,364B may carry at least oneelectrode373 configured to deliver the energy from thegenerator320 to the captured tissue. The engagement, or tissue-contacting, surface365A of upper jaw364A may carry a similar conductive-resistive matrix (i.e., a PTC material), or in some embodiments the surface may be a conductive electrode or an insulative layer, for example. Alternatively, the engagement surfaces of the jaws can carry any of the energy delivery components disclosed in U.S. Pat. No. 6,773,409, filed Oct. 22, 2001, entitled ELECTROSURGICAL JAW STRUCTURE FOR CONTROLLED ENERGY DELIVERY, the entire disclosure of which is incorporated herein by reference.

The first energy delivery surface365A and the second energy delivery surface365B may each be in electrical communication with thegenerator320. The first energy delivery surface365A and the second energy delivery surface365B may be configured to contact tissue and deliver electrosurgical energy to captured tissue which are adapted to seal or weld the tissue. Thecontrol unit325 regulates the electrical energy delivered byelectrical generator320 which in turn delivers electrosurgical energy to the first energy delivery surface365A and the second energy delivery surface365B. The energy delivery may be initiated by an activation button328 (FIG.12) operably engaged with thelever arm321 and in electrical communication with thegenerator320 viacable322. In one example embodiment, theelectrosurgical instrument310 may be energized by thegenerator320 by way of a foot switch329 (FIG.11). When actuated, thefoot switch329 triggers thegenerator320 to deliver electrical energy to theend effector326, for example. Thecontrol unit325 may regulate the power generated by thegenerator320 during activation. Although thefoot switch329 may be suitable in many circumstances, other suitable types of switches can be used.

As mentioned above, the electrosurgical energy delivered byelectrical generator320 and regulated, or otherwise controlled, by thecontrol unit325 may comprise radio frequency (RF) energy, or other suitable forms of electrical energy. Further, the opposing first and second energy delivery surfaces365A and365B may carry variable resistive positive temperature coefficient (PTC) bodies that are in electrical communication with thegenerator320 and thecontrol unit325. Additional details regarding electrosurgical end effectors, jaw closing mechanisms, and electrosurgical energy-delivery surfaces are described in the following U.S. patents and published patent applications: U.S. Pat. Nos. 7,087,054; 7,083,619; 7,070,597; 7,041,102; 7,011,657; 6,929,644; 6,926,716; 6,913,579; 6,905,497; 6,802,843; 6,770,072; 6,656,177; 6,533,784; and 6,500,312; and U.S. Patent Application Publication Nos. 2010/0036370 and 2009/0076506, all of which are incorporated herein in their entirety by reference and made a part of this specification.

In one example embodiment, thegenerator320 may be implemented as an electrosurgery unit (ESU) capable of supplying power sufficient to perform bipolar electrosurgery using radio frequency (RF) energy. In one example embodiment, the ESU can be a bipolar ERBE ICC 350 sold by ERBE USA, Inc. of Marietta, Ga. In some embodiments, such as for bipolar electrosurgery applications, a surgical instrument having an active electrode and a return electrode can be utilized, wherein the active electrode and the return electrode can be positioned against, adjacent to and/or in electrical communication with, the tissue to be treated such that current can flow from the active electrode, through the positive temperature coefficient (PTC) bodies and to the return electrode through the tissue. Thus, in various embodiments, theelectrosurgical system300 may comprise a supply path and a return path, wherein the captured tissue being treated completes, or closes, the circuit. In one example embodiment, thegenerator320 may be a monopolar RF ESU and theelectrosurgical instrument310 may comprise amonopolar end effector326 in which one or more active electrodes are integrated. For such a system, thegenerator320 may require a return pad in intimate contact with the patient at a location remote from the operative site and/or other suitable return path. The return pad may be connected via a cable to thegenerator320. In other embodiments, theoperator20 may provide subtherapeutic RF energy levels for purposes of evaluating tissue conditions and providing feedback in theelectrosurgical system300. Such feedback may be employed to control the therapeutic RF energy output of theelectrosurgical instrument310.

During operation ofelectrosurgical instrument300, the user generally grasps tissue, supplies energy to the captured tissue to form a weld or a seal (e.g., by actuatingbutton328 and/or pedal216), and then drives a tissue-cuttingelement371 at the distal end of the axiallymoveable member378 through the captured tissue. According to various embodiments, the translation of the axial movement of the axiallymoveable member378 may be paced, or otherwise controlled, to aid in driving the axiallymoveable member378 at a suitable rate of travel. By controlling the rate of the travel, the likelihood that the captured tissue has been properly and functionally sealed prior to transection with the cuttingelement371 is increased.

FIG.17 is a perspective view of one example embodiment of a surgical instrument system comprising a cordless electrical energysurgical instrument410. The electrosurgical system is similar to theelectrosurgical system300. The electrosurgical system can be configured to supply energy, such as electrical energy, ultrasonic energy, heat energy, or any combination thereof, to the tissue of a patient either independently or simultaneously as described in connection withFIGS.1 and11, for example. The electrosurgical instrument may utilize theend effector326 andelongated shaft314 described herein in conjunction with a cordlessproximal handle412. In one example embodiment, thehandle412 includes a generator circuit420 (seeFIG.18A). Thegenerator circuit420 performs a function substantially similar to that ofgenerator320. In one example embodiment, thegenerator circuit420 is coupled to a controller, such as a control circuit. In the illustrated embodiment, the control circuit is integrated into thegenerator circuit420. In other embodiments, the control circuit may be separate from thegenerator circuit420.

In one example embodiment, various electrodes in the end effector326 (including jaws364A,364B thereof) may be coupled to thegenerator circuit420. The control circuit may be used to activate thegenerator420, which may serve as an electrical source. In various embodiments, thegenerator420 may comprise an RF source, an ultrasonic source, a direct current source, and/or any other suitable type of electrical energy source, for example. In one example embodiment, abutton328 may be provided to activate thegenerator circuit420 to provide energy to theend effectors326,326.

FIG.18A is a side view of one example embodiment of thehandle412 of the cordlesssurgical instrument410. InFIG.18A, thehandle412 is shown with half of a first handle body removed to illustrate various components withinsecond handle body434. Thehandle412 may comprise a lever arm424 (e.g., a trigger) which may be pulled along apath33 around a pivot point. Thelever arm424 may be coupled to an axiallymoveable member478 disposed withinelongated shaft314 by a shuttle operably engaged to an extension oflever arm424. In one example embodiment, thelever arm424 defines a shepherd's hook shape comprising a distal member424aand a proximal member424b.

In one example embodiment, the cordless electrosurgical instrument comprises abattery437. Thebattery437 provides electrical energy to thegenerator circuit420. Thebattery437 may be any battery suitable for driving thegenerator circuit420 at the desired energy levels. In one example embodiment, thebattery437 is a 100 mAh, triple-cell Lithium Ion Polymer battery. The battery may be fully charged prior to use in a surgical procedure, and may hold a voltage of about 12.6V. Thebattery437 may have two fuses fitted to the cordlesselectrosurgical instrument410, arranged in line with each battery terminal. In one example embodiment, a charging port439 is provided to connect thebattery437 to a DC current source (not shown).

Thegenerator circuit420 may be configured in any suitable manner. In some embodiments, the generator circuit comprises an RF drive andcontrol circuit440 and a controller circuit482.FIG.18B illustrates an RF drive andcontrol circuit440, according to one embodiment.FIG.18B is a part schematic part block diagram illustrating the RF drive andcontrol circuitry440 used in this embodiment to generate and control the RF electrical energy supplied to theend effector326. As will be explained in more detail below, in this embodiment, thedrive circuitry440 is a resonant mode RF amplifier comprising a parallel resonant network on the RF amplifier output and the control circuitry operates to control the operating frequency of the drive signal so that it is maintained at the resonant frequency of the drive circuit, which in turn controls the amount of power supplied to theend effector326. The way that this is achieved will become apparent from the following description.

As shown inFIG.18B, the RF drive andcontrol circuit440 comprises the above describedbattery437 are arranged to supply, in this example, about 0V and about 12V rails. An input capacitor (C_in)442 is connected between the 0V and the 12V for providing a low source impedance. A pair of FET switches443-1 and443-2 (both of which are N-channel in this embodiment to reduce power losses) is connected in series between the 0V rail and the 12V rail. FET gate drive circuitry805 is provided that generates two drive signals—one for driving each of the two FETs443. The FETgate drive circuitry445 generates drive signals that causes the upper FET (443-1) to be on when the lower FET (443-2) is off and vice versa. This causes thenode447 to be alternately connected to the 12V rail (when the FET443-1 is switched on) and the 0V rail (when the FET443-2 is switched on).FIG.18B also shows the internal parasitic diodes448-1 and448-2 of the corresponding FETs443, which conduct during any periods that the FETs443 are open.

As shown inFIG.18B, thenode447 is connected to an inductor-inductorresonant circuit450 formed byinductor Ls452 andinductor L_m454. The FETgate driving circuitry445 is arranged to generate drive signals at a drive frequency (f_d) that opens and crosses the FET switches443 at the resonant frequency of the parallelresonant circuit450. As a result of the resonant characteristic of theresonant circuit450, the square wave voltage atnode447 will cause a substantially sinusoidal current at the drive frequency (f_d) to flow within theresonant circuit450. As illustrated inFIG.18B, theinductor L_m454 is the primary of atransformer455, the secondary of which is formed byinductor L_sec456. Theinductor L_sec456 of thetransformer455 secondary is connected to an inductor-capacitor-capacitor parallelresonant circuit457 formed byinductor L₂458, capacitor C₄460, andcapacitor C₂462. Thetransformer455 up-converts the drive voltage (V_d) across theinductor L_m454 to the voltage that is applied to the output parallelresonant circuit457. The load voltage (V_L) is output by the parallelresonant circuit457 and is applied to the load (represented by theload resistance R_load459 inFIG.18B) corresponding to the impedance of the forceps' jaws and any tissue or vessel gripped by theend effector326. As shown inFIG.18B, a pair of DC blocking capacitors C_bI480-1 and480-2 is provided to prevent any DC signal being applied to theload459.

In one embodiment, thetransformer455 may be implemented with a Core Diameter (mm), Wire Diameter (mm), and Gap between secondary windings in accordance with the following specifications:

• • Core Diameter, D (mm)
  • D=19.9×10−3
  • Wire diameter, W (mm) for 22 AWG wire
  • W=7.366×10−4
  • Gap between secondary windings, in gap=0.125
  • G=gap/25.4

In this embodiment, the amount of electrical power supplied to theend effector326 is controlled by varying the frequency of the switching signals used to switch the FETs443. This works because theresonant circuit450 acts as a frequency dependent (loss less) attenuator. The closer the drive signal is to the resonant frequency of theresonant circuit450, the less the drive signal is attenuated. Similarly, as the frequency of the drive signal is moved away from the resonant frequency of thecircuit450, the more the drive signal is attenuated and so the power supplied to the load reduces. In this embodiment, the frequency of the switching signals generated by the FETgate drive circuitry445 is controlled by acontroller481 based on a desired power to be delivered to theload459 and measurements of the load voltage (V_L) and of the load current (I_L) obtained by conventionalvoltage sensing circuitry483 andcurrent sensing circuitry485. The way that thecontroller481 operates will be described in more detail below.

In one embodiment, thevoltage sensing circuitry483 and thecurrent sensing circuitry485 may be implemented with high bandwidth, high speed rail-to-rail amplifiers (e.g., LMH6643 by National Semiconductor). Such amplifiers, however, consume a relatively high current when they are operational. Accordingly, a power save circuit may be provided to reduce the supply voltage of the amplifiers when they are not being used in thevoltage sensing circuitry483 and thecurrent sensing circuitry485. In one-embodiment, a step-down regulator (e.g., LT3502 by Linear Technologies) may be employed by the power save circuit to reduce the supply voltage of the rail-to-rail amplifiers and thus extend the life of thebattery437.

FIG.18C illustrates the main components of thecontroller481, according to one embodiment. In the embodiment illustrated inFIG.18C, thecontroller481 is a microprocessor based controller and so most of the components illustrated inFIG.16 are software based components. Nevertheless, a hardware basedcontroller481 may be used instead. As shown, thecontroller481 includes synchronous I,Q sampling circuitry491 that receives the sensed voltage and current signals from thesensing circuitry483 and485 and obtains corresponding samples which are passed to a power, V_rmsand I_rmscalculation module493. Thecalculation module493 uses the received samples to calculate the RMS voltage and RMS current applied to the load459 (FIG.18B;end effector326 and tissue/vessel gripped thereby) and from them the power that is presently being supplied to theload459. The determined values are then passed to afrequency control module495 and a medicaldevice control module497. The medicaldevice control module497 uses the values to determine the present impedance of theload459 and based on this determined impedance and a pre-defined algorithm, determines what set point power (P_set) should be applied to thefrequency control module495. The medicaldevice control module497 is in turn controlled by signals received from auser input module499 that receives inputs from the user (for example pressing buttons or activating the control levers114,110 on the handle104) and also controls output devices (lights, a display, speaker or the like) on thehandle104 via auser output module461.

Thefrequency control module495 uses the values obtained from thecalculation module493 and the power set point (P_set) obtained from the medicaldevice control module497 and predefined system limits (to be explained below), to determine whether or not to increase or decrease the applied frequency. The result of this decision is then passed to a squarewave generation module463 which, in this embodiment, increments or decrements the frequency of a square wave signal that it generates by 1 kHz, depending on the received decision. As those skilled in the art will appreciate, in an alternative embodiment, thefrequency control module495 may determine not only whether to increase or decrease the frequency, but also the amount of frequency change required. In this case, the squarewave generation module463 would generate the corresponding square wave signal with the desired frequency shift. In this embodiment, the square wave signal generated by the squarewave generation module463 is output to the FETgate drive circuitry445, which amplifies the signal and then applies it to the FET443-1. The FETgate drive circuitry445 also inverts the signal applied to the FET443-1 and applies the inverted signal to the FET443-2.

Theelectrosurgical instrument410 may comprise additional features as discussed with respect toelectrosurgical system300. Those skilled in the art will recognize thatelectrosurgical instrument410 may include arotation knob348, anelongated shaft314, and anend effector326. These elements function in a substantially similar manner to that discussed above with respect to theelectrosurgical system300. In one example embodiment, the cordlesselectrosurgical instrument410 may includevisual indicators435. Thevisual indicators435 may provide a visual indication signal to an operator. In one example embodiment, the visual indication signal may alert an operator that the device is on, or that the device is applying energy to the end effector. Those skilled in the art will recognize that thevisual indicators435 may be configured to provide information on multiple states of the device.

Over the years a variety of minimally invasive robotic (or “telesurgical”) systems have been developed to increase surgical dexterity as well as to permit a surgeon to operate on a patient in an intuitive manner. Robotic surgical systems can be used with many different types of surgical instruments including, for example, ultrasonic or electrosurgical instruments, as described herein. Example robotic systems include those manufactured by Intuitive Surgical, Inc., of Sunnyvale, Calif., U.S.A. Such systems, as well as robotic systems from other manufacturers, are disclosed in the following U.S. patents which are each herein incorporated by reference in their respective entirety: U.S. Pat. No. 5,792,135, entitled ARTICULATED SURGICAL INSTRUMENT FOR PERFORMING MINIMALLY INVASIVE SURGERY WITH ENHANCED DEXTERITY AND SENSITIVITY, U.S. Pat. No. 6,231,565, entitled ROBOTIC ARM DLUS FOR PERFORMING SURGICAL TASKS, U.S. Pat. No. 6,783,524, entitled ROBOTIC SURGICAL TOOL WITH ULTRASOUND CAUTERIZING AND CUTTING INSTRUMENT, U.S. Pat. No. 6,364,888, entitled ALIGNMENT OF MASTER AND SLAVE IN A MINIMALLY INVASIVE SURGICAL APPARATUS, U.S. Pat. No. 7,524,320, entitled MECHANICAL ACTUATOR INTERFACE SYSTEM FOR ROBOTIC SURGICAL TOOLS, U.S. Pat. No. 7,691,098, entitled PLATFORM LINK WRIST MECHANISM, U.S. Pat. No. 7,806,891, entitled REPOSITIONING AND REORIENTATION OF MASTER/SLAVE RELATIONSHIP IN MINIMALLY INVASIVE TELESURGERY, and U.S. Pat. No. 7,824,401, entitled SURGICAL TOOL WITH WRISTED MONOPOLAR ELECTROSURGICAL END EFFECTORS. Many of such systems, however, have in the past been unable to generate the magnitude of forces required to effectively cut and fasten tissue.

FIGS.19-46C illustrate example embodiments of robotic surgical systems. In some embodiments, the disclosed robotic surgical systems may utilize the ultrasonic or electrosurgical instruments described herein. Those skilled in the art will appreciate that the illustrated robotic surgical systems are not limited to only those instruments described herein, and may utilize any compatible surgical instruments. Those skilled in the art will further appreciate that while various embodiments described herein may be used with the described robotic surgical systems, the disclosure is not so limited, and may be used with any compatible robotic surgical system.

FIGS.19-25 illustrate the structure and operation of several example robotic surgical systems and components thereof.FIG.19 shows a block diagram of an example roboticsurgical system1000. Thesystem1000 comprises at least onecontroller508 and at least onearm cart510. Thearm cart510 may be mechanically coupled to one or more robotic manipulators or arms, indicated bybox512. Each of therobotic arms512 may comprise one or moresurgical instruments514 for performing various surgical tasks on apatient504. Operation of thearm cart510, including thearms512 andinstruments514 may be directed by aclinician502 from acontroller508. In some embodiments, asecond controller508′, operated by asecond clinician502′ may also direct operation of thearm cart510 in conjunction with thefirst clinician502′. For example, each of theclinicians502,502′ may controldifferent arms512 of the cart or, in some cases, complete control of thearm cart510 may be passed between theclinicians502,502′. In some embodiments, additional arm carts (not shown) may be utilized on thepatient504. These additional arm carts may be controlled by one or more of thecontrollers508,508′. The arm cart(s)510 andcontrollers508,508′ may be in communication with one another via acommunications link516, which may be any suitable type of wired or wireless communications link carrying any suitable type of signal (e.g., electrical, optical, infrared, etc.) according to any suitable communications protocol. Example implementations of robotic surgical systems, such as thesystem1000, are disclosed in U.S. Pat. No. 7,524,320 which has been herein incorporated by reference. Thus, various details of such devices will not be described in detail herein beyond that which may be necessary to understand various embodiments of the claimed device.

FIG.20 shows one example embodiment of arobotic arm cart520. Therobotic arm cart520 is configured to actuate a plurality of surgical instruments or instruments, generally designated as522 within awork envelope519. Various robotic surgery systems and methods employing master controller and robotic arm cart arrangements are disclosed in U.S. Pat. No. 6,132,368, entitled MULTI-COMPONENT TELEPRESENCE SYSTEM AND METHOD, the full disclosure of which is incorporated herein by reference. In various forms, therobotic arm cart520 includes a base524 from which, in the illustrated embodiment, threesurgical instruments522 are supported. In various forms, thesurgical instruments522 are each supported by a series of manually articulatable linkages, generally referred to as set-upjoints526, and arobotic manipulator528. These structures are herein illustrated with protective covers extending over much of the robotic linkage. These protective covers may be optional, and may be limited in size or entirely eliminated in some embodiments to minimize the inertia that is encountered by the servo mechanisms used to manipulate such devices, to limit the volume of moving components so as to avoid collisions, and to limit the overall weight of thecart520.Cart520 will generally have dimensions suitable for transporting thecart520 between operating rooms. Thecart520 may be configured to typically fit through standard operating room doors and onto standard hospital elevators. In various forms, thecart520 would preferably have a weight and include a wheel (or other transportation) system that allows thecart520 to be positioned adjacent an operating table by a single attendant.

FIG.21 shows one example embodiment of therobotic manipulator528 of therobotic arm cart520. In the example shown inFIG.21, therobotic manipulators528 may include alinkage530 that constrains movement of thesurgical instrument522. In various embodiments,linkage530 includes rigid links coupled together by rotational joints in a parallelogram arrangement so that thesurgical instrument522 rotates around a point inspace532, as more fully described in issued U.S. Pat. No. 5,817,084, the full disclosure of which is herein incorporated by reference. The parallelogram arrangement constrains rotation to pivoting about anaxis534a, sometimes called the pitch axis. The links supporting the parallelogram linkage are pivotally mounted to set-up joints526 (FIG.20) so that thesurgical instrument522 further rotates about anaxis534b, sometimes called the yaw axis. The pitch andyaw axes534a,534bintersect at theremote center536, which is aligned along ashaft538 of thesurgical instrument522. Thesurgical instrument522 may have further degrees of driven freedom as supported bymanipulator540, including sliding motion of thesurgical instrument522 along the longitudinal instrument axis “LT-LT”. As thesurgical instrument522 slides along the instrument axis LT-LT relative to manipulator540 (arrow534c),remote center536 remains fixed relative tobase542 ofmanipulator540. Hence, theentire manipulator540 is generally moved to re-positionremote center536.Linkage530 ofmanipulator540 is driven by a series ofmotors544. Thesemotors544 actively movelinkage530 in response to commands from a processor of a control system. As will be discussed in further detail below,motors544 are also employed to manipulate thesurgical instrument522.

FIG.22 shows one example embodiment of arobotic arm cart520′ having an alternative set-up joint structure. In this example embodiment, asurgical instrument522 is supported by analternative manipulator structure528′ between two tissue manipulation instruments. Those of ordinary skill in the art will appreciate that various embodiments of the claimed device may incorporate a wide variety of alternative robotic structures, including those described in U.S. Pat. No. 5,878,193, the full disclosure of which is incorporated herein by reference. Additionally, while the data communication between a robotic component and the processor of the robotic surgical system is primarily described herein with reference to communication between thesurgical instrument522 and the controller, it should be understood that similar communication may take place between circuitry of a manipulator, a set-up joint, an endoscope or other image capture device, or the like, and the processor of the robotic surgical system for component compatibility verification, component-type identification, component calibration (such as off-set or the like) communication, confirmation of coupling of the component to the robotic surgical system, or the like.

FIG.23 shows one example embodiment of acontroller518 that may be used in conjunction with a robotic arm cart, such as therobotic arm carts520,520′ depicted inFIGS.20-22. Thecontroller518 generally includes master controllers (generally represented as519 inFIG.23) which are grasped by the clinician and manipulated in space while the clinician views the procedure via astereo display521. A surgeon feed backmeter515 may be viewed via thedisplay521 and provide the surgeon with a visual indication of the amount of force being applied to the cutting instrument or dynamic clamping member. Themaster controllers519 generally comprise manual input devices which preferably move with multiple degrees of freedom, and which often further have a handle or trigger for actuating instruments (for example, for closing grasping saws, applying an electrical potential to an electrode, or the like).

FIG.24 shows one example embodiment of an ultrasonicsurgical instrument522 adapted for use with a robotic surgical system. For example, thesurgical instrument522 may be coupled to one of thesurgical manipulators528,528′ described hereinabove. As can be seen inFIG.24, thesurgical instrument522 comprises asurgical end effector548 that comprises anultrasonic blade550 and clamparm552, which may be coupled to anelongated shaft assembly554 that, in some embodiments, may comprise an articulation joint556.FIG.25 shows another example embodiment having anelectrosurgical instrument523 in place of the ultrasonicsurgical instrument522. Thesurgical instrument523 comprises asurgical end effector548 that comprises closable jaws551A,551B having energy deliver surfaces553A,553B for engaging and providing electrical energy to tissue between the jaws551A,551B. A tissue cutting element orknife555 may be positioned at the distal end of an axiallymovable member557 that may extend through theelongated shaft assembly554 to theinstrument mounting portion558.FIG.26 shows one example embodiment of aninstrument drive assembly546 that may be coupled to one of thesurgical manipulators528,528′ to receive and control thesurgical instruments522,523. Theinstrument drive assembly546 may also be operatively coupled to thecontroller518 to receive inputs from the clinician for controlling theinstrument522,523. For example, actuation (e.g., opening and closing) of theclamp arm552, actuation (e.g., opening and closing) of the jaws551A,551B, actuation of theultrasonic blade550, extension of theknife555 and actuation of the energy delivery surfaces553A,553B, etc. may be controlled through theinstrument drive assembly546 based on inputs from the clinician provided through thecontroller518. Thesurgical instrument522 is operably coupled to the manipulator by an instrument mounting portion, generally designated as558. Thesurgical instruments522 further include aninterface560 which mechanically and electrically couples theinstrument mounting portion558 to the manipulator.

FIG.27 shows another view of the instrument drive assembly ofFIG.26 including the ultrasonicsurgical instrument522.FIG.28 shows another view of the instrument drive assembly ofFIG.26 including theelectrosurgical instrument523. Theinstrument mounting portion558 includes aninstrument mounting plate562 that operably supports a plurality of (four are shown inFIG.26) rotatable body portions, driven discs orelements564, that each include a pair ofpins566 that extend from a surface of the drivenelement564. Onepin566 is closer to an axis of rotation of each drivenelements564 than theother pin566 on the same drivenelement564, which helps to ensure positive angular alignment of the drivenelement564. The drivenelements564 andpints566 may be positioned on anadapter side567 of theinstrument mounting plate562.

Interface560 also includes anadaptor portion568 that is configured to mountingly engage the mountingplate562 as will be further discussed below. Theadaptor portion568 may include an array of electrical connectingpins570, which may be coupled to a memory structure by a circuit board within theinstrument mounting portion558. Whileinterface560 is described herein with reference to mechanical, electrical, and magnetic coupling elements, it should be understood that a wide variety of telemetry modalities might be used, including infrared, inductive coupling, or the like.

FIGS.29-31 show additional views of theadapter portion568 of theinstrument drive assembly546 ofFIG.26. Theadapter portion568 generally includes aninstrument side572 and a holder side574 (FIG.29). In various embodiments, a plurality ofrotatable bodies576 are mounted to a floatingplate578 which has a limited range of movement relative to the surrounding adaptor structure normal to the major surfaces of theadaptor568. Axial movement of the floatingplate578 helps decouple therotatable bodies576 from theinstrument mounting portion558 when thelevers580 along the sides of the instrument mountingportion housing582 are actuated (SeeFIGS.24,25) Other mechanisms/arrangements may be employed for releasably coupling theinstrument mounting portion558 to theadaptor568. In at least one form,rotatable bodies576 are resiliently mounted to floatingplate578 by resilient radial members, which extend into a circumferential indentation about therotatable bodies576. Therotatable bodies576 can move axially relative toplate578 by deflection of these resilient structures. When disposed in a first axial position (toward instrument side572) therotatable bodies576 are free to rotate without angular limitation. However, as therotatable bodies576 move axially towardinstrument side572, tabs584 (extending radially from the rotatable bodies576) laterally engage detents on the floating plates so as to limit angular rotation of therotatable bodies576 about their axes. This limited rotation can be used to help drivingly engage therotatable bodies576 with drive pins586 of a correspondinginstrument holder portion588 of the robotic system, as the drive pins586 will push therotatable bodies576 into the limited rotation position until thepins586 are aligned with (and slide into)openings590.

Openings590 on theinstrument side572 andopenings590 on theholder side574 ofrotatable bodies576 are configured to accurately align the driven elements564 (FIGS.27,28) of theinstrument mounting portion558 with the drive elements592 of theinstrument holder588. As described above regarding inner andouter pins566 of drivenelements564, theopenings590 are at differing distances from the axis of rotation on their respectiverotatable bodies576 so as to ensure that the alignment is not 33 degrees from its intended position. Additionally, each of theopenings590 may be slightly radially elongated so as to fittingly receive thepins566 in the circumferential orientation. This allows thepins566 to slide radially within theopenings590 and accommodate some axial misalignment between theinstrument522,523 andinstrument holder588, while minimizing any angular misalignment and backlash between the drive and driven elements.Openings590 on theinstrument side572 may be offset by about 90 degrees from the openings590 (shown in broken lines) on theholder side574, as can be seen most clearly inFIG.31.

Various embodiments may further include an array of electrical connector pins570 located onholder side574 ofadaptor568, and theinstrument side572 of theadaptor568 may include slots594 (FIG.31) for receiving a pin array (not shown) from theinstrument mounting portion558. In addition to transmitting electrical signals between thesurgical instrument522,523 and theinstrument holder588, at least some of these electrical connections may be coupled to an adaptor memory device596 (FIG.30) by a circuit board of theadaptor568.

Adetachable latch arrangement598 may be employed to releasably affix theadaptor568 to theinstrument holder588. As used herein, the term “instrument drive assembly” when used in the context of the robotic system, at least encompasses various embodiments of theadapter568 andinstrument holder588 and which has been generally designated as546 inFIG.26. For example, as can be seen inFIG.26, theinstrument holder588 may include a firstlatch pin arrangement600 that is sized to be received in correspondingclevis slots602 provided in theadaptor568. In addition, theinstrument holder588 may further have second latch pins604 that are sized to be retained in corresponding latch devises606 in theadaptor568. SeeFIG.30. In at least one form, alatch assembly608 is movably supported on theadapter568 and is biasable between a first latched position wherein the latch pins600 are retained within theirrespective latch clevis606 and an unlatched position wherein the second latch pins604 may be into or removed from the latch devises606. A spring or springs (not shown) are employed to bias the latch assembly into the latched position. A lip on theinstrument side572 ofadaptor568 may slidably receive laterally extending tabs ofinstrument mounting housing582.

As described thedriven elements564 may be aligned with the drive elements592 of theinstrument holder588 such that rotational motion of the drive elements592 causes corresponding rotational motion of the drivenelements564. The rotation of the drive elements592 and drivenelements564 may be electronically controlled, for example, via therobotic arm612, in response to instructions received from theclinician502 via acontroller508. Theinstrument mounting portion558 may translate rotation of the drivenelements564 into motion of thesurgical instrument522,523.

FIGS.32-34 show one example embodiment of theinstrument mounting portion558 showing components for translating motion of the drivenelements564 into motion of thesurgical instrument522,523.FIGS.32-34 show the instrument mounting portion with ashaft538 having asurgical end effector610 at a distal end thereof. Theend effector610 may be any suitable type of end effector for performing a surgical task on a patient. For example, the end effector may be configured to provide RF and/or ultrasonic energy to tissue at a surgical site. Theshaft538 may be rotatably coupled to theinstrument mounting portion558 and secured by atop shaft holder646 and abottom shaft holder648 at acoupler650 of theshaft538.

In one example embodiment, theinstrument mounting portion558 comprises a mechanism for translating rotation of the various drivenelements564 into rotation of theshaft538, differential translation of members along the axis of the shaft (e.g., for articulation), and reciprocating translation of one or more members along the axis of the shaft538 (e.g., for extending and retracting tissue cutting elements such as555, overtubes and/or other components). In one example embodiment, the rotatable bodies612 (e.g., rotatable spools) are coupled to the drivenelements564. Therotatable bodies612 may be formed integrally with the drivenelements564. In some embodiments, therotatable bodies612 may be formed separately from the drivenelements564 provided that therotatable bodies612 and the drivenelements564 are fixedly coupled such that driving the drivenelements564 causes rotation of therotatable bodies612. Each of therotatable bodies612 is coupled to a gear train or gear mechanism to provide shaft articulation and rotation and clamp jaw open/close and knife actuation.

In one example embodiment, theinstrument mounting portion558 comprises a mechanism for causing differential translation of two or more members along the axis of theshaft538. In the example provided inFIGS.32-34, this motion is used to manipulate articulation joint556. In the illustrated embodiment, for example, theinstrument mounting portion558 comprises a rack and pinion gearing mechanism to provide the differential translation and thus the shaft articulation functionality. In one example embodiment, the rack and pinion gearing mechanism comprises afirst pinion gear614 coupled to arotatable body612 such that rotation of the corresponding drivenelement564 causes thefirst pinion gear614 to rotate. Abearing616 is coupled to therotatable body612 and is provided between the drivenelement564 and thefirst pinion gear614. Thefirst pinion gear614 is meshed to afirst rack gear618 to convert the rotational motion of thefirst pinion gear614 into linear motion of thefirst rack gear618 to control the articulation of thearticulation section556 of theshaft assembly538 in aleft direction620L. Thefirst rack gear618 is attached to a first articulation band622 (FIG.32) such that linear motion of thefirst rack gear618 in a distal direction causes thearticulation section556 of theshaft assembly538 to articulate in theleft direction620L. Asecond pinion gear626 is coupled to anotherrotatable body612 such that rotation of the corresponding drivenelement564 causes thesecond pinion gear626 to rotate. Abearing616 is coupled to therotatable body612 and is provided between the drivenelement564 and thesecond pinion gear626. Thesecond pinion gear626 is meshed to asecond rack gear628 to convert the rotational motion of thesecond pinion gear626 into linear motion of thesecond rack gear628 to control the articulation of thearticulation section556 in aright direction620R. Thesecond rack gear628 is attached to a second articulation band624 (FIG.33) such that linear motion of thesecond rack gear628 in a distal direction causes thearticulation section556 of theshaft assembly538 to articulate in theright direction620R. Additional bearings may be provided between the rotatable bodies and the corresponding gears. Any suitable bearings may be provided to support and stabilize the mounting and reduce rotary friction of shaft and gears, for example.

In one example embodiment, theinstrument mounting portion558 further comprises a mechanism for translating rotation of the drivenelements564 into rotational motion about the axis of theshaft538. For example, the rotational motion may be rotation of theshaft538 itself. In the illustrated embodiment, a firstspiral worm gear630 coupled to arotatable body612 and a secondspiral worm gear632 coupled to theshaft assembly538. A bearing616 (FIG.17) is coupled to arotatable body612 and is provided between a drivenelement564 and the firstspiral worm gear630. The firstspiral worm gear630 is meshed to the secondspiral worm gear632, which may be coupled to theshaft assembly538 and/or to another component of theinstrument522,523 for which longitudinal rotation is desired. Rotation may be caused in a clockwise (CW) and counter-clockwise (CCW) direction based on the rotational direction of the first and second spiral worm gears630,632. Accordingly, rotation of the firstspiral worm gear630 about a first axis is converted to rotation of the secondspiral worm gear632 about a second axis, which is orthogonal to the first axis. As shown inFIGS.32-33, for example, a CW rotation of the secondspiral worm gear632 results in a CW rotation of theshaft assembly538 in the direction indicated by634CW. A CCW rotation of the secondspiral worm gear632 results in a CCW rotation of theshaft assembly538 in the direction indicated by634CCW. Additional bearings may be provided between the rotatable bodies and the corresponding gears. Any suitable bearings may be provided to support and stabilize the mounting and reduce rotary friction of shaft and gears, for example.

In one example embodiment, theinstrument mounting portion558 comprises a mechanism for generating reciprocating translation of one or more members along the axis of theshaft538. Such translation may be used, for example to drive a tissue cutting element, such as555, drive an overtube for closure and/or articulation of theend effector610, etc. In the illustrated embodiment, for example, a rack and pinion gearing mechanism may provide the reciprocating translation. Afirst gear636 is coupled to arotatable body612 such that rotation of the corresponding drivenelement564 causes thefirst gear636 to rotate in a first direction. Asecond gear638 is free to rotate about apost640 formed in theinstrument mounting plate562. Thefirst gear636 is meshed to thesecond gear638 such that thesecond gear638 rotates in a direction that is opposite of thefirst gear636. In one example embodiment, thesecond gear638 is a pinion gear meshed to arack gear642, which moves in a liner direction. Therack gear642 is coupled to a translatingblock644, which may translate distally and proximally with therack gear642. Thetranslation block644 may be coupled to any suitable component of theshaft assembly538 and/or theend effector610 so as to provide reciprocating longitudinal motion. For example, thetranslation block644 may be mechanically coupled to thetissue cutting element555 of the RFsurgical device523. In some embodiments, thetranslation block644 may be coupled to an overtube, or other component of theend effector610 orshaft538.

FIGS.35-37 illustrate an alternate embodiment of theinstrument mounting portion558 showing an alternate example mechanism for translating rotation of the drivenelements564 into rotational motion about the axis of theshaft538 and an alternate example mechanism for generating reciprocating translation of one or more members along the axis of theshaft538. Referring now to the alternate rotational mechanism, a firstspiral worm gear652 is coupled to a secondspiral worm gear654, which is coupled to a thirdspiral worm gear656. Such an arrangement may be provided for various reasons including maintaining compatibility with existingrobotic systems1000 and/or where space may be limited. The firstspiral worm gear652 is coupled to arotatable body612. The thirdspiral worm gear656 is meshed with a fourthspiral worm gear658 coupled to theshaft assembly538. A bearing760 is coupled to arotatable body612 and is provided between a drivenelement564 and the first spiral worm gear738. Another bearing760 is coupled to arotatable body612 and is provided between a drivenelement564 and the thirdspiral worm gear652. The thirdspiral worm gear652 is meshed to the fourthspiral worm gear658, which may be coupled to theshaft assembly538 and/or to another component of theinstrument522,523 for which longitudinal rotation is desired. Rotation may be caused in a CW and a CCW direction based on the rotational direction of the spiral worm gears656,658. Accordingly, rotation of the thirdspiral worm gear656 about a first axis is converted to rotation of the fourthspiral worm gear658 about a second axis, which is orthogonal to the first axis. As shown inFIGS.36 and37, for example, the fourthspiral worm gear658 is coupled to theshaft538, and a CW rotation of the fourthspiral worm gear658 results in a CW rotation of theshaft assembly538 in the direction indicated by634CW. A CCW rotation of the fourthspiral worm gear658 results in a CCW rotation of theshaft assembly538 in the direction indicated by634CCW. Additional bearings may be provided between the rotatable bodies and the corresponding gears. Any suitable bearings may be provided to support and stabilize the mounting and reduce rotary friction of shaft and gears, for example.

Referring now to the alternate example mechanism for generating reciprocating translation of one or more members along the axis of theshaft538, theinstrument mounting portion558 comprises a rack and pinion gearing mechanism to provide reciprocating translation along the axis of the shaft538 (e.g., translation of atissue cutting element555 of the RF surgical device523). In one example embodiment, athird pinion gear660 is coupled to arotatable body612 such that rotation of the corresponding drivenelement564 causes thethird pinion gear660 to rotate in a first direction. Thethird pinion gear660 is meshed to arack gear662, which moves in a linear direction. Therack gear662 is coupled to a translatingblock664. The translatingblock664 may be coupled to a component of thedevice522,523, such as, for example, thetissue cutting element555 of the RF surgical device and/or an overtube or other component which is desired to be translated longitudinally.

FIGS.38-42 illustrate an alternate embodiment of theinstrument mounting portion558 showing another alternate example mechanism for translating rotation of the drivenelements564 into rotational motion about the axis of theshaft538. InFIGS.38-42, theshaft538 is coupled to the remainder of the mountingportion558 via acoupler676 and abushing678. Afirst gear666 coupled to arotatable body612, a fixedpost668 comprising first andsecond openings672, first and secondrotatable pins674 coupled to the shaft assembly, and a cable670 (or rope). The cable is wrapped around therotatable body612. One end of thecable670 is located through atop opening672 of the fixedpost668 and fixedly coupled to a toprotatable pin674. Another end of thecable670 is located through abottom opening672 of the fixedpost668 and fixedly coupled to a bottomrotating pin674. Such an arrangement is provided for various reasons including maintaining compatibility with existingrobotic systems1000 and/or where space may be limited. Accordingly, rotation of therotatable body612 causes the rotation about theshaft assembly538 in a CW and a CCW direction based on the rotational direction of the rotatable body612 (e.g., rotation of theshaft538 itself). Accordingly, rotation of therotatable body612 about a first axis is converted to rotation of theshaft assembly538 about a second axis, which is orthogonal to the first axis. As shown inFIGS.38-39, for example, a CW rotation of therotatable body612 results in a CW rotation of theshaft assembly538 in the direction indicated by634CW. A CCW rotation of therotatable body612 results in a CCW rotation of theshaft assembly538 in the direction indicated by634CCW. Additional bearings may be provided between the rotatable bodies and the corresponding gears. Any suitable bearings may be provided to support and stabilize the mounting and reduce rotary friction of shaft and gears, for example.

FIGS.43-46A illustrate an alternate embodiment of theinstrument mounting portion558 showing an alternate example mechanism for differential translation of members along the axis of the shaft538 (e.g., for articulation). For example, as illustrated inFIGS.43-46A, theinstrument mounting portion558 comprises adouble cam mechanism680 to provide the shaft articulation functionality. In one example embodiment, thedouble cam mechanism680 comprises first andsecond cam portions680A,680B. First andsecond follower arms682,684 are pivotally coupled to corresponding pivot spools686. As therotatable body612 coupled to thedouble cam mechanism680 rotates, thefirst cam portion680A acts on thefirst follower arm682 and thesecond cam portion680B acts on thesecond follower arm684. As thecam mechanism680 rotates thefollower arms682,684 pivot about the pivot spools686. Thefirst follower arm682 may be attached to a first member that is to be differentially translated (e.g., the first articulation band622). Thesecond follower arm684 is attached to a second member that is to be differentially translated (e.g., the second articulation band624). As thetop cam portion680A acts on thefirst follower arm682, the first and second members are differentially translated. In the example embodiment where the first and second members are therespective articulation bands622 and624, theshaft assembly538 articulates in aleft direction620L. As thebottom cam portion680B acts of thesecond follower arm684, theshaft assembly538 articulates in aright direction620R. In some example embodiments, twoseparate bushings688,690 are mounted beneath the respective first andsecond follower arms682,684 to allow the rotation of the shaft without affecting the articulating positions of the first andsecond follower arms682,684. For articulation motion, these bushings reciprocate with the first andsecond follower arms682,684 without affecting the rotary position of the jaw902.FIG.46A shows thebushings688,690 and thedual cam assembly680, including the first andsecond cam portions680B,680B, with the first andsecond follower arms682,684 removed to provide a more detailed and clearer view.

In various embodiments, theinstrument mounting portion558 may additionally comprise internal energy sources for driving electronics and provided desired ultrasonic and/or RF frequency signals to surgical tools.FIGS.46B-46C illustrate one embodiment of atool mounting portion558′ comprising internal power and energy sources. For example, surgical instruments (e.g.,instruments522,523) mounted utilizing thetool mounting portion558′ need not be wired to an external generator or other power source. Instead, the functionality of thevarious generators20,320 described herein may be implemented on board the mountingportion558.

As illustrated inFIGS.46B-46C, theinstrument mounting portion558′ may comprise adistal portion702. Thedistal portion702 may comprise various mechanisms for coupling rotation ofdrive elements612 to end effectors of the varioussurgical instruments522,523, for example, as described herein above. Proximal of thedistal portion702, theinstrument mounting portion558′ comprises an internal direct current (DC) energy source and an internal drive andcontrol circuit704. In the illustrated embodiment, the energy source comprises a first andsecond battery706,708. In other respects, thetool mounting portion558′ is similar to the various embodiments of thetool mounting portion558 described herein above.

Thecontrol circuit704 may operate in a manner similar to that described above with respect togenerators20,320. For example, when anultrasonic instrument522 is utilized, thecontrol circuit704 may provide an ultrasonic drive signal in a manner similar to that described above with respect togenerator20. Also, for example, when anRF instrument523 orultrasonic instrument522 capable of providing a therapeutic or non-therapeutic RF signal is used, thecontrol circuit704 may provide an RF drive signal, for example, as described herein above with respect to themodule23 ofgenerator20 and/or thegenerator300. In some embodiments, thecontrol circuit704 may be configured in a manner similar to that of thecontrol circuit440 described herein above with respect toFIGS.18B-18C.

Various embodiments described herein comprise an articulatable shaft. When using an articulatable shaft, components running through the shaft from the end effector must be flexible, so as to flex when the shaft articulates. In various embodiments, this can be accomplished by utilizing waveguides that have flexible portions. For example,FIG.47 illustrates a schematic cross-sectional view of a portion of one example embodiment of an ultrasonicmedical instrument1500 comprising first, second and third waveguide portions. InFIG.47, the hand piece and the sheath-articulation control knobs, etc. of the ultrasonicmedical instrument1500 are omitted for clarity. In the example embodiment shown inFIG.47, the ultrasonicmedical instrument1500 comprises a medicalultrasonic waveguide1502 for transmitting ultrasonic energy from a transducer (not shown inFIG.47) to anultrasonic blade1544. The medicalultrasonic waveguide1502 has a length and includes first, second andthird waveguide portions1504,1506 and1508. Thesecond waveguide portion1506 is located lengthwise between the first andthird waveguide portions1504 and1508; thefirst waveguide portion1504 is located proximal thesecond waveguide portion1506; and thethird waveguide portion1508 is located distal thesecond waveguide portion1506. The first andthird waveguide portions1504 and1508 each have a larger transverse area and thesecond waveguide portion1506 has a smaller transverse area. Thesecond waveguide portion1506 is more bendable than either of the first andthird waveguide portions1504 and1508. It is further noted that ultrasonic vibration can be any one, or any combination, of longitudinal, transverse, and torsional vibration. In some embodiments, thesection1506 may have a circular cross-section (e.g., a uniform cross-sectional radius).

In some embodiments the secondbendable waveguide portion1506 may not have a uniform cross-sectional radius. For example,FIG.47A illustrates cross sections for two example embodiments of thewaveguide portion1506. Thewaveguide portion1506′ is illustrated in relation to twoaxes1509,1511, also shown inFIG.47. In various embodiments, thewaveguide portion1506′ may have a cross sectional length alongaxis1511 that is less than its cross sectional dimension alongaxis1509. In some embodiments, the cross sectional length along theaxis1509 may be equal to the cross sectional length of theother waveguide portions1504,1506. Thewaveguide portion1506′ may be bendable along theaxis1509. Referring now towaveguide portion1506″, its cross sectional lengths along theaxis1509,1511 may be the same, providing thewaveguide portion1506″ with a greater range of directions for bending.

In some example embodiments, the medicalultrasonic waveguide1502 is a monolithic (e.g., theblade portion1544 is integral to the waveguide1502). Also, in some example embodiments, the medicalultrasonic waveguide1502 includes first and secondlongitudinal vibration antinodes1510 and1512. Thefirst waveguide portion1504 may transition to thesecond waveguide portion1506 proximate the first longitudinal vibration antinode1510; and thesecond waveguide portion1506 may transition to thethird waveguide portion1508 proximate the secondlongitudinal vibration antinode1512. In some example embodiments, as illustrated byFIG.47, thesecond waveguide portion1506 is substantially ½ of a resonant-longitudinal-wavelength long.

In one example application of the embodiment ofFIG.47, the ultrasonicmedical instrument1500 also includes a user-actuated articulatedsheath1514 which surrounds the medicalultrasonic waveguide1502. In various example embodiments, the medicalultrasonic waveguide1502 includes three (meaning at least three)longitudinal vibration nodes1516 located, one each, on the first, second andthird waveguide portions1504,1506 and1508. It is noted that one or more additional longitudinal vibration nodes may, or may not, be present between any one or two of the threelongitudinal vibration nodes1516. In one modification, thesheath1514 contacts (e.g., directly contacts or indirectly contacts through at least one interveningmember1517 such as a silicone intervening member) the first, second andthird waveguide portions1504,1506 and1508 at a corresponding one of the threelongitudinal vibration nodes1516. In one example, thesheath1514 includes a rigidfirst sheath portion1518 contacting thefirst waveguide portion1504 at the first longitudinal vibration node (theleftmost node1516 ofFIG.47), a flexiblesecond sheath portion1520 contacting thesecond waveguide portion1506 at the second longitudinal vibration node (themiddle node1516 ofFIG.47), and a rigidthird sheath portion1522 contacting thethird waveguide portion1508 at the third longitudinal vibration node (therightmost node1516 ofFIG.47). In some example embodiments, thesheath1514 has only two articulation positions (e.g., straight and fully articulated). In other example embodiments, thesheath1514 has a number of intermediate bent positions between a straight position and a fully articulated position depending on the number of energy efficient curves thewaveguide1502 can be formed to. In some example embodiments, such energy efficient curves minimize vibrational energy going into non-longitudinal vibrational modes.

FIG.48 illustrates a schematic cross-sectional view of a portion of one example embodiment of an ultrasonicmedical instrument1524 comprising first andsecond waveguide portions1530,1532, where thefirst waveguide portion1530 spans multiple ½ resonant longitudinal wavelengths. In the example embodiment show inFIG.48, a medicalultrasonic waveguide1526 includes at least twolongitudinal vibration nodes1528 located on thefirst waveguide portion1530. In one variation, asheath1534 contacts (e.g., directly contacts or indirectly contacts through at least one interveningmember1536 such as a silicone intervening member) thefirst waveguide portion1530 at the at-least-twolongitudinal vibration nodes1528. In some example embodiments, thesheath1534 includes tworigid sheath portions1538 and1542 and oneflexible sheath portion1540, wherein theflexible sheath portion1540 contacts thefirst waveguide portion1530 at least one of the twolongitudinal vibration nodes1528, and wherein theflexible sheath portion1540 is disposed between the tworigid sheath portions1538 and1542. In one example embodiment, the tworigid sheath portions1538 and1542 each contact thesecond waveguide portion1532 at a corresponding one of the at-least-twolongitudinal vibration nodes1528.

Referring now toFIG.47, thewaveguide1502 may comprise ablade portion1544 adapted to contact and ultrasonically treat patient tissue. Theblade portion1544 may be disposed at a distal end of the waveguide1502 (e.g., distal of thethird blade portion1508 of the blade1502). In one example embodiment, thesurgical instrument1500 may also comprise a user-actuatedclamp arm1546 pivotally attached to thesheath1514,1534 proximate theblade portion1544, wherein theclamp arm1546 and the medicalultrasonic waveguide1502 at least in part define an ultrasonicsurgical shears1548. The tissue pad and clamping arm control mechanism has been omitted fromFIG.47. Referring again toFIG.48, the medicalultrasonic waveguide1526 may also comprise ablade portion1545, similar to theblade portion1544, and disposed at a distal end of thefirst waveguide portion1532. Theblade portion1545 may also be adapted to contact and ultrasonically treat patient tissue. Theinstrument1524 ofFIG.48 may also comprise aclamp arm1546, defining, with theblade portion1545, an ultrasonicsurgical shears1548.

In various example embodiments, certain portions of thewaveguides1502,1526 are substantially rigid. For example, first andthird portions1504 and1508 of thewaveguide1502 may be substantially rigid. Thefirst portion1532 of thewaveguide1526 may be substantially rigid. Referring again toFIG.47, the medicalultrasonic waveguide1502 may include first andsecond neck portions1550 and1552 joining, respectively, the first andsecond waveguide portions1504 and1506 and the second andthird waveguide portions1506 and1508. (Asimilar neck portion1552 may join the first andsecond waveguide portions1530,1532 of thewaveguide1526.)

In one modification, the medicalultrasonic waveguide1502 is substantially cylindrical from thefirst waveguide portion1504 to thethird waveguide portion1508, wherein the first, second andthird waveguide portions1504,1506 and1508 each have a substantially constant diameter, and wherein the diameter of thesecond waveguide portion1506 is smaller than the diameter of either of the first andthird waveguide portions1504 and1508. In some example embodiments, the diameter of thesecond waveguide portion1506 is between substantially one and two millimeters, and the diameter of the first and third waveguide portions is between substantially three and five millimeters. In one choice of materials, the medicalultrasonic waveguide1502 consists essentially of a titanium alloy. In one modification, the medicalultrasonic waveguide1502 includes first and secondlongitudinal vibration antinodes1510 and1512, and thefirst neck portion1550 is disposed proximate the first longitudinal vibration antinode1510 and thesecond neck portion1552 is disposed proximate the secondlongitudinal vibration antinode1512.

FIG.49 illustrates a schematic cross-sectional view of one example embodiment of anultrasonic waveguide1554 for use with a medical instrument and comprising first and second waveguide portions, where afirst waveguide portion1556 is joined to asecond waveguide portion1558 by a dowel press fit. In the example illustrated inFIG.49, thesecond waveguide portion1558 is also coupled to athird waveguide portion1560 by a dowel press fit. In various example embodiments, thesecond waveguide portion1558 consists essentially of titanium or nitinol. In the same or a different illustration, the length of thesecond waveguide portion1558 is less than ½ wavelength (a wavelength being the length of a resonant-longitudinal-wavelength of the medical ultrasonic waveguide which depends essentially on the material of the waveguide and the frequency at which it is run) and in one example is less than ⅛ wave.

FIG.50 illustrates a schematic cross-sectional view of one example embodiment of anultrasonic waveguide1564 for use with a medical instrument. Like thewaveguide1554, thewaveguide1564 is not a monolithic waveguide. Thewaveguide1564 may comprise first andsecond waveguide portions1564,1566, where thefirst waveguide portion1564 is joined to thesecond waveguide1566 portion by a ball-and-socket type attachment. Thesecond waveguide portion1566 may also be joined to athird waveguide portion1568 in any suitable manner. In the example ofFIG.50, thesecond waveguide portion1566 is joined to thethird waveguide portion1568 via a dowel press fit. Other attachments between waveguide portions are left to those skilled in the art.

FIG.51 illustrates a schematic cross-sectional view of a portion of another embodiment of an ultrasonicmedical instrument1570 comprising a medical ultrasonic waveguide1572 having a length and including aproximal waveguide portion1574 and adistal waveguide portion1576. Theproximal waveguide portion1574 has a larger transverse area and thedistal waveguide portion1576 has a smaller transverse area. Thedistal waveguide portion1576 bends more easily than does theproximal waveguide portion1574. Thedistal waveguide portion1576 includes adistal end portion1580 adapted to contact and ultrasonically treat patient tissue. In various example embodiments, the additional ½ wave needed to neck up and create the larger diameter end effector of the embodiment ofFIG.47 is eliminated making it possible to place the articulation joint closer to the distal end of the ultrasonicmedical instrument1570. The embodiments, applications, etc. shown inFIGS.47-50 are equally applicable (without the presence of the third waveguide portion) to the embodiment ofFIG.51.

FIG.52 illustrates one embodiment of anultrasonic blade1000 comprising a proximalstraight section1003 and a distalcurved section1004.FIGS.53-56 illustrate additional views of theultrasonic blade1000. In various embodiments, theblade1000 may be balanced by manipulating features of thecurved section1004 such as, for example, a radius of curvature, a subtended angle, etc. Asymmetric blades, such as theblade1004, may be considered balanced when vibrational modes within theblade1000 are purely and/or substantially longitudinal (e.g., in the direction of the longitudinal axis1002). Each vibrational mode may correspond to a resonant frequency and/or wavelength of theblade1000. In some example applications, an asymmetric blade, such as theblade1000, may be considered balanced when, for a desired vibrational mode (e.g., resonant wavelength) the transverse component of displacement at the proximal end is reduced such that under operating conditions, the blade behaves in a manner similar to that of a symmetric design. In various example embodiments, some or all of the proximalstraight section1003 may make up all or a part of a waveguide extending proximally to a transducer, such as thetransducer16 described herein above.

In various example embodiments, theblade1000 may be balanced by configuring theblade1000 so that a node or anti-node is positioned at a point oftangency1006 between thestraight section1003 and thecurved section1004. The point oftangency1006 is a position where thestraight section1003 is tangent to the curve of thecurved section1004. In example embodiments where the curvature of thecurved section1004 is constant, the point oftangency1006 may be at a point where thestraight section1003 meets thecurved section1004.FIGS.58 and59 illustrate two exampleultrasonic blades1010,1012 balanced as described herein. The positions ofvarious nodes1016 andantinodes1014 are indicated. The point of tangency between thecurved section1004 andstraight section1003 of each of theblades1010 and1012 is indicated by1006. As illustrated,blade1010 has acurved section1004 with a length corresponding to one half of one wavelength at the illustrated mode. Anantinode1014 is positioned at the point oftangency1006. In contrast, theblade1012 has acurved section1004 with a length corresponding to one quarter of one wavelength at the illustrated mode. Anode1016 is shown at the point oftangency1006.

Configuring an ultrasonic blade, such as1000,1010,1012, etc., such that a node or anti-node is positioned at the point oftangency1006 may be accomplished in any suitable manner. For example, it will be appreciated that when an ultrasonic blade, such as theblades1000,1010,1012 is bent material tension due to the bending causes the speed of sound to increase in thecurved section1004. This brings about a corresponding increase in both the wavelengths of resonant frequencies at different modes and an increase in the phase velocity of ultrasonic vibrations traveling through the bent orcurved section1004. As a result, nodes and antinodes in thecurved section1004 are farther from one another than in thestraight section1003, as illustrated inFIGS.57-58. When thecurved section1004 of theblade1000 is also used to treat tissue, the increase in length may increase the active area of the blade1000 (e.g., the area that is ultrasonically activated, so as to transmit energy to tissue).

The increased distance between nodes and antinodes in thecurved section1004 can also complicate the precise placement of a node or anti-node (e.g., as nodes and anti-nodes are separated by multiples of one-half of one wavelength). In various example embodiments, the changes in material properties of theblade1000 due to bending may be taken into account by setting the a radius of curvature of thecurved section1004 based on an angle subtended by thecurved section1004. In some example embodiments, other factors may be considered as well. The radius of curvature and subtended angle for different curved sections are illustrated byFIGS.56 and59.FIG.56 illustrates one embodiment of theultrasonic blade1000 illustrating the radius ofcurvature1010 and subtendedangle1008 of thecurved section1004 of theblade1000.FIG.59 illustrates another embodiment of anultrasonic blade1000′ having acurved section1004 with adifferent subtended angle1012 and radius ofcurvature1014.

The radius of curvature, subtended angle, and other properties of any given curved blade may be selected according to any suitable factors such that the blade is balanced with a node or antinode at the point of tangency. For example, in various embodiments, the radius of curvature may be selected as a function of, the subtended angle, a number of wavelengths, or fractions thereof, in the curved section at the resonant frequency of the relevant mode, and the phase velocity of ultrasonic vibrations in the blade at the resonant frequency of the relevant mode. For example, these factors may be considered as indicated according to Equation (1) below:

$\begin{array}{cc}\mathrm{radius}\mathrm{of}\mathrm{curvature}=\frac{nc\pi }{4\theta {f_0\left(\pi -{\theta }^2\right)}^{0.5}}& \left(1\right)\end{array}$
In Equation (1), f₀is a resonant frequency of theultrasonic blade1000,1000′,1010,1012 at the relevant mode; θ is the angle subtended by thecurved section1004; n is a number of quarter wavelengths in thecurved section1004; and c is a phase velocity of ultrasonic vibrations in the ultrasonic blade at the resonant frequency of the relevant mode.

FIG.60 illustrates achart1019 showing the balance of an example blade having a one-half wavelength curvedsection1004, for example, similar to theblade1000′ ofFIG.59. Thehorizontal axis1022 of the chart corresponds to a radius of curvature measured in inches while thevertical axis1024 corresponds to the subtended angle of thecurved section1004 measured in degrees. The surface plot shows the ratio of transverse displacement to longitudinal displacement at a proximal end of the measured blade, which provides an indication of balance.Line1020 corresponds to a plot of Equation (1). It can be seen that the areas of highest balance roughly correspond to Equation (1).

FIGS.61-66 illustrate various example embodiments of anarticulatable shaft1030 that may be articulated utilizing nodal flanges. Theshaft1030 ofFIGS.61-66 are shown in conjunction with anultrasonic blade1038, it will be appreciated that theshaft1030 may also be used for various other types of surgical instruments. Referring now toFIG.61, theshaft1030 comprises aproximal tube1032 and aflexible portion1034. Theflexible portion1034, for example, may be formed byslots1035 formed in theshaft1030 to allow bending. Various other bending mechanisms and/or configurations may also be utilized. Distal of the flexible portion, anend effector1036 may be coupled to theshaft1030. Theend effector1036, as illustrated inFIG.61 comprises anultrasonic blade1038.

FIG.62 illustrates one embodiment of theshaft1030 with portions of theshaft1030 transparent so as to show awaveguide1040 coupled to theultrasonic blade1038. Thewaveguide1040 comprises abendable portion1046, for example, similar to thebendable portions1506,1530,1576, etc., described herein above. Thebendable portion1046 of thewaveguide1040 may be positioned longitudinally at about the same position as theflexible portion1034 of theshaft1030. As shown, thewaveguide1040 additionally comprises a plurality offlanges1042,1044,1048. Theflanges1042,1044,1048 may be positioned at nodes of thewaveguide1040 and may be coupled to theshaft1030 in any suitable manner. At least one of the flanges (e.g., flange1042) may be positioned proximally from the bendable portion1045, and at least one of the flanges (e.g., flange1048) may be positioned distally from the bendable portion1045.FIG.62 also shows anoptional flange1044 positioned in thebendable portion1046. Such flanges in the bendable portion1045 may be desirable for longerbendable portions1046.

According to various example embodiments, theshaft1030 may comprisecontrol members1050,1052 for controlling articulation.FIGS.63-65 illustrate one example embodiment of thewaveguide1040 showing the operation ofcontrol members1050,1052. Referring toFIG.63, thecontrol member1050 may be coupled toflange1048 and extend proximally through theflange1042.Control member1052 may also be coupled to theflange1048 and extend proximally through theflange1042. Proximal translation of thecontrol member1050 may pull theflange1048 andblade1038 proximally away from thelongitudinal axis1002 and towards thecontrol member1050, as shown inFIG.64. When thecontrol member1050 is pulled proximally, as shown inFIG.64, thecontrol member1052 may be pulled distally. In some embodiments, the additional flange1044 (shown inFIG.62) may be included so as to prevent thecontrol member1052 from contacting thewaveguide1040 away from a node. Referring now toFIG.65, thecontrol member1052 may be pulled proximally to pull theflange1048 andblade1038 proximally away from thelongitudinal axis1002 towards thecontrol member1052. In the example configuration shown inFIG.65, thecontrol member1050 behaves in a manner similar to that described above with respect to controlmember1052 inFIG.64.

Differential translation of thecontrol members1050,1052 may be accomplished in any suitable manner. For example, when theshaft1030 is utilized in the context of a surgical robot, the members1220,1222 may be differentially translated utilizing any of the methods and/or mechanisms described herein above with respect toFIGS.32-46C.FIGS.66-67 illustrate one example embodiment of a manual or handheldsurgical instrument1064 utilizing theshaft1030 described above. As shown inFIG.66, thecontrol members1050,1052 are coupled to respective rack gears1063,1065. Between, and in mechanical communication with, the rack gears1063,1065 is apinion gear1068. Alever1066 is coupled to thepinion gear1068 such that rotation of thelever1066 causes rotation of thepinion gear1068. As shown, rotation of thepinion gear1068 in a first direction causes distal translation of thecontrol member1050 and proximal translation of thecontrol member1052. Rotation of thepinion gear1068 in a second direction opposite the first direction causes proximal translation of thecontrol member1050 and distal translation of thecontrol member1052.FIG.67 shows theinstrument1064 coupled to theshaft1030. The rack gears1063,1065 andpinion gear1068 may be contained withoutarticulation housing1070 that is, in turn, coupled to ahandle1072. Thelever1066 is extends from thearticulation housing1070 and may be manipulated by a clinician.

FIG.68 illustrates one embodiment of theend effector1036 and a distal portion of theshaft1030 showing apivotable clamp arm1058. Thepivotable clamp arm1058 may be pivotably coupled to aclamp arm member1060 at ahinge interface1062. Theclamp arm member1060 may be coupled to theflange1048, for example, via a connectingmember1056. In some example embodiments, theclamp arm member1060 may be a flange positioned at a node of thewaveguide1040, obviating the need for aseparate flange1048 and clamparm member1060. As illustrated inFIG.66, thehinge interface1062 may be offset from thelongitudinal axis1002. A translatingmember1063 may be coupled to theclamp arm1058 at a position also offset from thelongitudinal axis1002 and opposite thehinge interface1062. Distal translation of the translatingmember1063 may cause theclamp arm1058 to pivot about thehinge interface1062 away from thelongitudinal axis1002 to an open position. Subsequent proximal translation of the translatingmember1063 may pivot theclamp arm1058 back towards thelongitudinal axis1002 to the closed position shown inFIG.66. In some example embodiments, anoptional spring1061 may bias theclamp arm1058 to an open position. Proximal translation of the translatingmember1063 may oppose the bias of the spring and pivot theclamp arm1058 back towards thelongitudinal axis1002 to the closed position shown inFIG.66.

It will be appreciated that the translatingmember1063 may be translated distally and proximally according to any suitable method. For example, when theshaft1030 is used in conjunction with a manual or hand held surgical instrument, the translatingmember1063 may be translated distally and proximally in a manner similar to that described herein above with respect to the reciprocating tubular actuatingmember58 of theinstrument10 and/or theaxially moving member378 of theinstrument300. Also, for example, when theshaft1030 is used in conjunction with a surgical robot, the translatingmember1063 may be translated distally and proximally in a manner similar to that described above with respect to thetissue cutting element555 of theinstrument310.

Various example embodiments of shafts for use with surgical instruments may comprise biased inner shafts and rigid outer shafts. The respective shafts may be translatable relative to one another such that when the biased inner shaft extends beyond the rigid outer shaft, an end effector coupled to the flexible inner shaft pivots away from the longitudinal axis of the shaft.FIGS.69-71 illustrate one example embodiment of ashaft1070 for a surgical instrument having a rigidouter shaft1072 and a biasedinner shaft1074. As shown inFIG.69, theinner shaft1074 is positioned substantially within theouter shaft1074 such that theshaft1070 is substantially straight along thelongitudinal axis1002. InFIG.70, theinner shaft1074 has begun to translate distally relative to theouter shaft1072. It will be appreciated that illustrated translation may be brought about either by distal translation of theinner shaft1074, proximal translation of theouter shaft1072, or some combination of both. As the biasedinner shaft1074 extends from the rigidouter shaft1072 and is no longer held straight, theinner shaft1074 may begin to pivot away from thelongitudinal axis1002 in the direction of its bias (down relative toFIG.70).FIG.71 shows theinner shaft1074 extended distally further showing additional bias.

The biasedinner shaft1074 may be biased in any suitable manner. For example,FIGS.72-74 illustrate one example embodiment of the biasedinner shaft1074 where biasing is provided byleaf springs1076. For example, theinner shaft1074 may be a straight tube made of metal or another suitable surgical material.Slots1078 may make the tube flexible. Leaf springs may be installed at about the position of theslots1078 to bias theinner tube1074, as illustrated inFIG.74. Although the leave springs1076 are shown positioned outside of theinner shaft1074, they may be positioned on the inside of theinner shaft1074 in some example embodiments.

It will be appreciated that the inner andouter shafts1074,1072 may be translated relative to one another according to any suitable method or mechanism. For example, when theshaft1130 is used in conjunction with a manual or hand held surgical instrument, the translatingmembers1136,1137 may be translated distally and proximally in a manner similar to that described herein above with respect to the reciprocating tubular actuatingmember58 of theinstrument10 and/or theaxially moving member378 of theinstrument300. Also, for example, when theshaft1130 is used in conjunction with a surgical robot, the translatingmembers1136,1137 may be translated distally and proximally in a manner similar to that described above with respect to thetissue cutting element555 of theinstrument310.

FIGS.75-76 illustrate another embodiment of ashaft1080 comprising a biasedinner shaft1090 and a rigidouter shaft1088. Theshaft1080 is illustrated in conjunction with anultrasonic blade1082 acoustically coupled to awaveguide1086 extending proximally from theblade1082. Thewaveguide1082 may comprise abendable portion1087, such as thebendable portions1506,1530,1576, etc., described herein above. Thebendable portion1087 of thewaveguide1082 may allow thewaveguide1082 to flex with the biasedinner shaft1090, as illustrated. Referring now toFIG.76, the biasedinner shaft1090 is shown translated distally relative to the rigidouter shaft1088. As illustrated, the biasedinner shaft1090 flexes away from thelongitudinal axis1002. Thebendable portion1087 of thewaveguide1086 is shown to be bent, thus allowing theultrasonic blade1082 to also pivot. The biasedinner shaft1090 may be biased in any suitable manner. For example, in some embodiments the biasedinner shaft1090 may be biased by a leaf spring, as illustrated above with respect toFIGS.72-74. In other example embodiments, the biasedinner shaft1090 may be constructed of a resilient material such as rubber, metal or plastic that has been pre-formed and/or bent to the shaft shown inFIG.76.FIGS.77 and78 illustrate one example embodiment of theshaft1080 and biasedinner shaft1090 used with analternate waveguide1091. As illustrated thewaveguide1090 comprises aproximal portion1100, abendable portion1096 and anintermediate portion1094. Theintermediate portion1094 may be coupled to anultrasonic blade1092, as shown.

FIGS.79-81 illustrate another example embodiment of ashaft1120 for use with a surgical instrument, the shaft having a rigidouter shaft1136 and a biasedinner shaft1128. With theshaft1120, anultrasonic transducer1122 may be present in the biasedinner shaft1128 distal from abiased pivot point1134. Thetransducer1122 may operate to drive anultrasonic blade1124, for example, in a manner similar to that described above with respect to thetransducer16 described herein above. The biasedinner shaft1128 may comprise aproximal member1132 and adistal member1130 pivotably joined at thebiased pivot point1134. Because thetransducer1122 is located proximally from thepivot point1134, it may not be necessary for a waveguide to cross thepivot point1134. This may provide flexibility to use different pivot point designs. For example, in one embodiment, thepivot point1134 comprises apin1135 coupling themembers1130,1132. Thepivot point1134 may be biased in any suitable manner. For example, in some embodiments, thepivot point1134 may comprise atorsion spring1137. Theshaft1120 may articulate in a manner similar to that of theshafts1070,1080 described above. For example, inFIG.79, theinner shaft1128 is translated distally relative to theouter shaft1136 such that the bias of theinner shaft1128 causes it to pivot about thepivot point1134 away from thelongitudinal axis1002 as shown. InFIG.80, theinner shaft1128 is translated proximally such that thepivot point1134 is nearly within theouter shaft1136. InFIG.81, thepivot point1134 is within theouter shaft1136 and the inner shaft1128 (and ultrasonic blade1124) are substantially in alignment with thelongitudinal axis1002.

Various example embodiments of shafts with biased inner shafts and rigid outer shafts may be utilized in conjunction with a pivotable clamp arm, such as the clamp arm shown inFIG.66. For example, theclamp arm member1060 ofFIG.66 may be coupled to a flange of a waveguide and/or to a distal end of one or more of the flexibleinner shafts1074,1090,1128. Theclamp arm1058 may be operated as described above.

FIGS.82-83 illustrate one embodiment of adistal portion1140 of a surgical instrument comprising a curvedultrasonic blade1142. The curvedultrasonic blade1142 and ashaft1144 may be translatable relative to one another along thelongitudinal axis1002. The curvature of theultrasonic blade1142 may be determined to balance the blade, for example, as described above with respect toblades1000,1000′,1010 and1012. When theblade1142 is translated distally relative to theshaft1144, as shown inFIG.82, theblade1142 may demonstrate a curved section1146 curved away from thelongitudinal axis1002. Theblade1142 andshaft1144 may also have an additional state, shown inFIG.83, whereby theblade1142 is retracted proximally relative to theshaft1144 such that theblade1142 is within theshaft1144. In some example embodiments, theblade1142 may contact an inner portion of theshaft1144 in the state shown inFIG.83. In this way, the curved section1146 may exhibit a curvature in use (e.g., radius of curvature and subtended angle) that does not fit through adistal opening1150 of theshaft1144. For example, theblade1142 may be resilient such that the curvature of the curved section1146 increases upon extension distally from theshaft1144. Also, in some embodiment, theblade1142 may define a secondcurved section1148. Curvature of the second curved section may be opposite that of the curved section1146.

Non-Limiting Examples

Various embodiments described herein are directed to ultrasonic blades. In one embodiment, an ultrasonic blade may comprise a proximally positioned straight section extending along a longitudinal axis and a distally positioned curved section coupled to the straight section and curved away from the longitudinal axis. The curved section may define a radius of curvature and subtend a first angle. A point of tangency between the curved section and the straight section is located at a predetermined position. In one embodiment, the point of tangency may be located at a node of the ultrasonic blade, an anti-node, or between the node and the anti-node of the ultrasonic blade, and any combination thereof.

Also, various embodiments are directed to surgical instruments comprising an end effector comprising an ultrasonic blade and a shaft extending proximally from the end effector, where the shaft comprises a flexible portion. Certain embodiments also comprise a waveguide acoustically coupled to the ultrasonic blade and extending proximally through the shaft. In one embodiment, the waveguide may comprise a bendable waveguide portion at about the flexible shaft portion. The waveguide may further comprise first and second flanges. The first flange may be positioned at a node of the waveguide distal from the bendable waveguide portion and may be coupled to the interior of the shaft. The second flange may be positioned at a node of the waveguide proximate from the bendable waveguide portion and may also be coupled to the interior of the shaft. A control member may be coupled to the first flange and may extend proximally through the second flange and shaft such that proximal translation of the control member pulls the first flange proximally, causing the shaft and waveguide to pivot away from the longitudinal axis towards the first control member.

Various embodiments are also directed to surgical instruments comprising an end effector, an outer shaft and an inner shaft at least partially within the outer shaft, where both shafts extend along a longitudinal axis. In one embodiment, the inner shaft may comprise a biased portion that is biased to bend away from the longitudinal axis in a first direction. Further, the inner and outer shafts may be translatable relative to one another from a first position to a second position. In the first position, the biased portion of the inner shaft is within the outer shaft and the inner shaft is substantially straight. In the second position, the biased portion of the inner shaft is outside of and distally positioned from the outer shaft such that the biased portion of the inner shaft is bent away from the longitudinal axis.

Additionally, various embodiments are directed to surgical instruments comprising a shaft extending along a longitudinal axis and an ultrasonic blade. The ultrasonic blade may comprise a proximally positioned straight section and a distally positioned curved section. The ultrasonic blade may be translatable along the longitudinal axis relative to the shaft from a first position where the curved section of the blade extends from a distal end of the shaft to a second position where the curved section of the blade is at least partially contained within the shaft.

Applicant also owns the following patent applications that are each incorporated by reference in their respective entireties:

U.S. patent application Ser. No. 13/536,271, filed on Jun. 28, 2012 and entitled FLEXIBLE DRIVE MEMBER, now U.S. Pat. No. 9,204,879;

U.S. patent application Ser. No. 13/536,288, filed on Jun. 28, 2012 and entitled MULTI-FUNCTIONAL POWERED SURGICAL DEVICE WITH EXTERNAL DISSECTION FEATURES, now U.S. Patent Application Publication No. 2014/0005718;

U.S. patent application Ser. No. 13/536,295, filed on Jun. 28, 2012 and entitled ROTARY ACTUATABLE CLOSURE ARRANGEMENT FOR SURGICAL END EFFECTOR, now U.S. Pat. No. 9,119,657;

U.S. patent application Ser. No. 13/536,326, filed on Jun. 28, 2012 and entitled SURGICAL END EFFECTORS HAVING ANGLED TISSUE-CONTACTING SURFACES, now U.S. Pat. No. 9,289,256;

U.S. patent application Ser. No. 13/536,303, filed on Jun. 28, 2012 and entitled INTERCHANGEABLE END EFFECTOR COUPLING ARRANGEMENT, now U.S. Pat. No. 9,028,494;

U.S. patent application Ser. No. 13/536,393, filed on Jun. 28, 2012 and entitled SURGICAL END EFFECTOR JAW AND ELECTRODE CONFIGURATIONS, now U.S. Patent Application Publication No. 2014/0005640;

U.S. patent application Ser. No. 13/536,362, filed on Jun. 28, 2012 and entitled MULTI-AXIS ARTICULATING AND ROTATING SURGICAL TOOLS, now U.S. Pat. No. 9,125,662; and

U.S. patent application Ser. No. 13/536,417, filed on Jun. 28, 2012 and entitled ELECTRODE CONNECTIONS FOR ROTARY DRIVEN SURGICAL TOOLS, now U.S. Pat. No. 9,101,385.

It will be appreciated that the terms “proximal” and “distal” are used throughout the specification with reference to a clinician manipulating one end of an instrument used to treat a patient. The term “proximal” refers to the portion of the instrument closest to the clinician and the term “distal” refers to the portion located furthest from the clinician. It will further be appreciated that for conciseness and clarity, spatial terms such as “vertical,” “horizontal,” “up,” or “down” may be used herein with respect to the illustrated embodiments. However, surgical instruments may be used in many orientations and positions, and these terms are not intended to be limiting or absolute.

Various embodiments of surgical instruments and robotic surgical systems are described herein. It will be understood by those skilled in the art that the various embodiments described herein may be used with the described surgical instruments and robotic surgical systems. The descriptions are provided for example only, and those skilled in the art will understand that the disclosed embodiments are not limited to only the devices disclosed herein, but may be used with any compatible surgical instrument or robotic surgical system.

Reference throughout the specification to “various embodiments,” “some embodiments,” “one example embodiment,” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one example embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one example embodiment,” or “in an embodiment” in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics illustrated or described in connection with one example embodiment may be combined, in whole or in part, with features, structures, or characteristics of one or more other embodiments without limitation.

While various embodiments herein have been illustrated by description of several embodiments and while the illustrative embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications may readily appear to those skilled in the art. For example, each of the disclosed embodiments may be employed in endoscopic procedures, laparoscopic procedures, as well as open procedures, without limitations to its intended use.

It is to be understood that at least some of the figures and descriptions herein have been simplified to illustrate elements that are relevant for a clear understanding of the disclosure, while eliminating, for purposes of clarity, other elements. Those of ordinary skill in the art will recognize, however, that these and other elements may be desirable. However, because such elements are well known in the art, and because they do not facilitate a better understanding of the disclosure, a discussion of such elements is not provided herein.

While several embodiments have been described, it should be apparent, however, that various modifications, alterations and adaptations to those embodiments may occur to persons skilled in the art with the attainment of some or all of the advantages of the disclosure. For example, according to various embodiments, a single component may be replaced by multiple components, and multiple components may be replaced by a single component, to perform a given function or functions. This application is therefore intended to cover all such modifications, alterations and adaptations without departing from the scope and spirit of the disclosure as defined by the appended claims.

Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated materials does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.

Claims (17)

What is claimed is:

1. An articulatable surgical instrument comprising:

a shaft extending along a longitudinal axis; and

an end effector configured to treat tissue, the end effector comprising a curved ultrasonic blade positioned within the shaft and translatable relative to the shaft along the longitudinal axis;

wherein the curved ultrasonic blade comprises a proximal portion that is curved in a first direction away from the longitudinal axis, an intermediate portion that is curved in a second direction away from the longitudinal axis and opposite the first direction, and a distal portion that extends from the intermediate portion in the first direction, the ultrasonic blade manufactured such that the curvature of the proximal portion and the curvature of the intermediate portion are balanced to both have a vibrational mode purely in the direction of the longitudinal axis.

2. The articulatable surgical instrument ofclaim 1, wherein the curvature of the proximal portion and the curvature of the intermediate portion both comprise a node and/or anti-node that occurs at a point of tangency when the ultrasonic blade is driven at a resonant frequency.

3. The articulatable surgical instrument ofclaim 1, wherein the distal portion of the ultrasonic blade extends beyond the shaft in a lateral direction relative to the longitudinal axis, when in a first configuration when the ultrasonic blade protracts distally.

4. The articulatable surgical instrument ofclaim 3, wherein the distal portion of the ultrasonic blade is configured to fully retract within the shaft when in a second configuration when the ultrasonic blade retracts proximally.

5. The articulable surgical instrument ofclaim 4, wherein the distal portion of the ultrasonic blade contacts an inner portion of the shaft when in the second configuration.

6. The articulatable surgical instrument ofclaim 4, wherein the ultrasonic blade is resilient such that the distal portion increases upon extension distally from the shaft in the first configuration.

7. An end effector of a surgical instrument comprising:

a shaft extending along a longitudinal axis; and

a curved ultrasonic blade positioned within the shaft and translatable relative to the shaft along the longitudinal axis;

wherein the curved ultrasonic blade comprises a proximal portion that is curved in a first direction away from the longitudinal axis, an intermediate portion that is curved in a second direction away from the longitudinal axis and opposite the first direction, and a distal portion that extends from the intermediate portion in the first direction, wherein the ultrasonic blade is manufactured such that the curvature of the proximal portion and the curvature of the intermediate portion are balanced to both have a vibrational mode purely in the direction of the longitudinal axis.

8. The end effector ofclaim 7, wherein the curvature of the proximal portion and the curvature of the intermediate portion both comprise a node and/or anti-node that occurs at a point of tangency when the ultrasonic blade is driven at a resonant frequency.

9. The end effector ofclaim 7, wherein the distal portion of the ultrasonic blade extends beyond the shaft in a lateral direction relative to the longitudinal axis, when in a first configuration when the ultrasonic blade protracts distally.

10. The end effector ofclaim 9, wherein the distal portion of the ultrasonic blade is configured to fully retract within the shaft when in a second configuration when the ultrasonic blade retracts proximally.

11. The end effector ofclaim 10, wherein the distal portion of the ultrasonic blade contacts an inner portion of the shaft when in the second configuration.

12. The end effector ofclaim 10, wherein the ultrasonic blade is resilient such that the distal portion increases upon extension distally from the shaft in the first configuration.

13. A system comprising:

a generator configured to delivery ultrasonic energy; and

a surgical instrument coupled to the generator, the surgical instrument comprising:

a shaft extending along a longitudinal axis; and

an end effector configured to treat tissue, the end effector comprising a curved ultrasonic blade positioned within the shaft and translatable relative to the shaft along the longitudinal axis;

wherein the curved ultrasonic blade comprises a proximal portion that is curved in a first direction away from the longitudinal axis, an intermediate portion that is curved in a second direction away from the longitudinal axis and opposite the first direction, and a distal portion that extends from the intermediate portion in the first direction, wherein the ultrasonic blade is manufactured such that the curvature of the proximal portion and the curvature of the intermediate portion are balanced to both have a vibrational mode purely in the direction of the longitudinal axis.

14. The system ofclaim 13, wherein the curvature of the proximal portion and the curvature of the intermediate portion both comprise a node and/or anti-node that occurs at a point of tangency when the ultrasonic blade is driven at a resonant frequency.

15. The system ofclaim 13, wherein the distal portion of the ultrasonic blade extends beyond the shaft in a lateral direction relative to the longitudinal axis, when in a first configuration when the ultrasonic blade protracts distally.

16. The system ofclaim 15, wherein the distal portion of the ultrasonic blade is configured to fully retract within the shaft when in a second configuration when the ultrasonic blade retracts proximally.

17. The system ofclaim 16, wherein the distal portion of the ultrasonic blade contacts an inner portion of the shaft when in the second configuration.

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